ARNOLD ARBORETUM

Gray Htfbarium Harvard University 1952

HARVARD UNIVERSITY

ARNOLDIA

A continuation of the

Bulletin of Popular Information

VOLUME XII 1952

PUBLISHED BY THE

ARNOLD ARBORETUM

JAMAICA PLAIN, MASSACHUSETTS

Digitized by the Internet Archive in 2017 with funding from BHL-SIL-FEDLINK

https://archive.org/details/arnoldiaarno_9

A continuation of the Bulletin of Popular Information of the Arnold Arboretum, Harvard University

V^OLUME 12

MARCH 7, 1952

Number 1

FORTY-FIVE OF THE BEST TREES FOR MASSACHUSETTS GARDENS*

Massachusetts Ims lon^ been a horticultural center where many new plants were first introduced into cultivation. In colonial times this was true of fruit varieties, a little bit later it was true of many rare greenhouse plants, and since the beginning of the twentieth centur,v it has been true of trees and shrubs suitable for enriching the ornamental plantings about the home. Now, there are hundreds of trees being grown in the state, so many that it is frequently most confusing to the home owner to select a few for his own garden. This list of -lo of the ^%est” trees for Massachusetts gardens is prepared in the hope of stimulating gardeners into becoming acquainted with some of the more unusual trees that are now commereialfv available.

One fact should be kept in mind however, before taking the following list at its face value. There are many trees commonly grown in Massachusetts, some native and some exotic, that will always be serviceable. New trees may be glow- ingly described in the catalogues, but these common favorites have served relia- bly for many years and probably will continue to do so for many more. These are among the trees that every gardener should know and use for one reason or another. Nothing is meant to be implied in the following discussion of the 4-5 selected types that would cast a shadow of doubt on the serviceability of these, a few of which are listed on pages 19 and 20.

* This list was prepared at the request of the Horticultural Committee of the Garden Club Federation of Massachusetts, five of the trees to be discussed at each of the nine meetings of the horticultural chairmen throughout the year. Because of wide-spread interest in this list it is here produced for the benefit of ARNOLDIA subscribers, and is a companion list to that published in ARNOLDIA for March 11, 19.51, describing forty-five of the best shrubs for Massachusetts gardens. It is not perfect, and many may take exception to it. However, it does include forG^-five top-notch trees that can be used more in our gardens today. Most important, aU are available i)i 1952 from local nurseries!

Kee|)iii<( these trees very clearly in mind, let us consider some that are not as ji easily found, either in fjardens or commercial nurseries. It is especially important j to note that each plant in the following list is available from at least one of the : listed nurserymen. It was impossible to contact all the nurserymen in the state ; so there are undoubtedly many other sources for these plants than those listed. Since they are available, your local nurseryman can obtain them for you if he will, j It is useless tt) become enthusiastic about a plant that is unobtainable. Each j one of these is available in 1952. Consequently, the gardeners of the state are j urged to become acquainted with some of these better trees, buy a few that are i hardy (for all are not completely hardy in all parts of the state) for planting in i

order to become better acquainted with and interest of the plantings about their

Forty-five of the Best Trees

Abies homolepis 1,4,6,9,10

koreana 4 Acer circinatum 5,10

griseum 5,6

palmatum atropurpureum 1-10

platanoides columnare 1,5, 6, 7, 8 “Crimson King” 1,2, 3, 4, 7, 8

rubrum columnare 1,2,4,6,7,8,9,10 Albizzia julibrissin rosea 5,6,10 Amelanchier laevis 4,5,8 Cedrus libani 4, 5, 6, 7 Cercidiphyllum japonicum 2, 5, 6, 7, 8, 9 Cercis canadensis alba 5,6 Elaeagnus angustifolia 2,4,6,7,8,10 kA’odia danielli 5,6

Gleditsia triacanthos “Moraine” 1 -4,6-1 Halesia monticola 4,5,6,7,8, 10 Ilex pedunculosa 5,10 Kalopanax pictus 6,8 Koelreuteria paniculata 1,4, 5, 6 Larix leptolepis 4,7,8 Magnolia denudata 6

virginiana 5,6,7,8,9,10

Sources for Trees

1.

2.

m, and in this way increase the beauty homes.

for Massachusetts Gardens

Malus “Dorothea” 5,8

hupehensis 4, 5, 6, 7, 8, 9

purpurea aldenhamensis 6,7 lemoinei 3,5,6,8,10

toringoides 6 Oxydendrum arboreum 1-8,10 Parrotia persica 5 Phellodendron amurense 4,5,6 Picea asperata 4,6

omorika 4, 5, 6, 9 Pinus bungeana 5,6

thunbergi 2, 4, 6, 7, 8 Prunus avium plena 6

serrulata “Amanogawa” 5,7,8

- “Fugenzo” 7

“Kwanzan” 1,2, 7, 8, 9 f

Pseudolarix amabilis 5 f

Sciadopitys verticillata 3,5,7 f

Sophora japonica 1,4,5,6,7,8,10 |

Stewartia koreana 5 j'

Syringa amurensis japonica 1,3-7, 9 I

Thuja plicata 4,6,10 |

I I

Listed

3.

Adams Nursery, Inc., Westfield, Mass.

Bay State Nurseries, North Abington, Mass. Cherry Hill Nurseries, West Newbury, Mass.

I

4-. Harlan P. Kelsey, Inc., East Boxford, Mass.

5. Kingsville Nurseries, Kingsville, Maryland

6. Henry Kohankie ik Son, Painesville, Ohio

7. Littlefield-Wyman Nurseries, 227 Centre Ave., Abington, Mass.

8. Weston Nurseries, Inc., Weston, Mass.

9. 'Wyman’s Framingham Nurseries, Framingham, Mass.

10. Tingle Nurseries, Pittsville, Maryland

Forty-five of the Best Trees for Massachusetts Gardens

Hardiness note: Trees listed as hardy in Zones 2, 3 and 4 are hardy through- out most of Massachusetts; those hardy in Zone 5 can be safely grown only in the southern, eastern, and southeastern parts of the state.

Abies homolepis 90' Zone 4 Nikko Fir

One of the best firs for ornamental planting. Easily distinguished from other firs because of the horizontal decurrent lines along the one year twigs. Dark green, vigorous an excellent conifer for use in any landscape where it can be given plenty of room to grow naturally. Like all other firs, this Japanese native is stiffly pyramidal in outline with definitely horizontal branches.

Abies koreana oO' Zone 3 Korean Fir

This tree grows very well but few trees in this country have reached their ma- ture height. It grows more slowly than some of the others and might be the only one considered for small gardens because of this fact. It is stiff and formal but the whitish undersurface of the needles shows to good advantage. A native of Korea and introduced into America in 1918 by the Arnold Arboretum, it too, is stiffly pyramidal in habit.

Acer circinatum 23' Zone 3 Vine Maple

A native maple of the Pacific Coast adapted for use in gardens because of its small, compact size and its abilit.v to grow in partially shaded situations especially under evergreens. It is somewhat similar in habit to A. palmatum except that its stems twist and turn in a most interesting manner, thus giving rise to its name. The wood is very tough the Indians, according to legend, used the wood to make fish hooks.

Acer griseum 23' Zone 3 Paperbark Maple

Very difficult to propagate in quantity because only a very small proportion of the seed develops. Otherwise, it could easily be one of the most popular maples. The bark is cinnamon-brown and exfoliates in paper-thin strips similar to that of certain birches. This bark characteristic is easily noticeable from some distance

<a\vay, makinj? this tree of outstandinf? interest throu«?hout the entire year. It is lioped that a reliable method can be found for propagating this plant on a large scale for it certainly merits wide use and has been growing in the Arnold Arbo- retum for fifty years.

Acer palmatum atropurpureum '20' Zone o Bloodleaf Japanese Maple i This is one of the best forms of the Japanese Maple. Frequently these forms i are not asexually propagated but grown from seed, a very poor practice. The N true Bloodleaf Japanese Maple keeps its good red foliage color throughout the i entire growing season and is fairly hardy in Massachusetts. It is well worth try- ); ing to obtain the true form, since so many of the substitutes either will not keep 'j

the foliage color or are injured by winter cold. j'

i,

Acer platanoides columnare 90' Zone 3 Columnar Norway Maple |j

This columnar variety of the commonly planted Norway Maple, has all the !j good traits of the latter and in addition a very narrow habit. Trees 20-30 feet in ! height may be less than ten feet in diameter of branch spread. For tall, narrow ji accent points on the small property or for trees along narrow streets, this city i dweller is excellent. !

I

Acer platanoides “Crimson King” 90' Zone 3 I

This is a seedling of Acer platanoides schicedleri, originating at Orleans, France, t in the nurseries of Barbier and Company. It was first introduced into America |! by the Gulf Stream Nurseries, Wachapreague, \Jrginia, in 1948, and has been ' patented (No. 735) by this company. This tree is far superior to the Schwedler Maple, in that it keeps its rich purplish red foliage color throughout the entire i growing season. Up to the time this clone became available, the Schwedler | Maple had proved popular for its colored foliage; but, as many know, this color, j|; while a pronounced red in the early spring, gradually turns greenish in the sum- mer. During the four growing seasons that ‘^Crimson King” has been growing ; in the Arnold Arboretum, it has kept its color uniform throughout the entire | period of growth, from spring to fall. Consequently, it is an excellent shade tree . in situations where its colored foliage is thought desirable. |

Acer rubrum columnare 60' Zone 3 Columnar Red Maple ^

Like the Red Maple in foliage and texture, but densely upright in habit. It fj is not as narrow as the Columnar Norway Maple but is a fast growing type. |

Albizzia julibrissin rosea 36' Zone 5 Silk Tree i

'riiis tree of exceedingly dainty foliage and Howers is now threatened in the |i South with a serious wilt disease which kills the tree. This fungus occurs in the f soil and infests the tree through the roots. Many clones are being tried and some ;i

U I

!

PLATE J

The L rribreiia Hrla/iopUyi r,(^rtxrli‘'xta. an ex< e.ient den-.e p, rarn Cii

e verir reerj ipern rn en .

have been found to be very resistant to the disease. Fortunately it may not affect : trees ‘rrown in the northern states at all. The hardy variety rosea is probably like ; the species in that it is difficult to get established at first. Since vegetative growth ^ is made late in the season it can be killed somewhat during very cold winters.

Altliough it can be grown on many soils, the Arnold Arboretum has found that | it does well on poor, dry, gravelly soils and so has an important use. I

Being a legume, the seed is borne in small flat pods. The flowers are conspicu- I ous, not because of petals (which are insignificant) but because of inch long pink I colored stamens, borne in ball-like clusters. The plant has the very desirable I trait of opening its flowers consecutively throughout the summer months. The plants growing in Boston start to bloom about July loth and are continuously in bloom until early September a long flowering period which cannot be matched ' by any other northern ornamental tree. The leaves fall at the first frost without changing color.

A splendid ornamental tree, very much worth experimenting with in the North i (hardy variety only) until just the right soil and winter protection are found so > that it will live over the first few winters and become a sizeable plant. The tree blooms early in life, sometimes when the seedlings are only two to three years old. Propagation is easily accomplished by 3 inch root cuttings made in very early spring using roots that are inch or more in diameter. Smaller roots do not root nearly as well.

Amelanchier laevis 36' Zone 4 Allegany Serviceberry

A small native tree, delightfully prominent in the very early spring when its profuse white flowers appear before the leaves. The orange to scarlet autumn ' color brings it into prominence a second time in the year, and its light gray bark is especially distinctive. x\dmittedly a native, this tree has several qualities (other than its short-lasting flowers) suggesting that it should be used more in natural- ized plantings.

Cedrus libani 1^20' Zone .5 Cedar of Lebanon

Widely grown throughout the South, it was not until the Arnold Arboretum sent a special expedition to Asia Minor in 1903 to collect seed at the highest al- I titudes where these trees were native that plants could be perfectly hardy in the northeastern United States. Mature trees are very wide at the base, but trees of 30-40 years of age have about the same dimensions as Abies coficolor, although | they are not nearly as dense. The dark green foliage, stiff habit, picturesque and | rigidly upright cones, some of which are usually on the tree since they take two years to mature, give this tree a popular interest. Frequent reference is made to | it in the Bible and Solomon’s Temple was supposed to have been built with its | massive timbers. It does not produce much shade and certainly is very formal in |

liabit, but apparently has (rreat popular api)eal nevertheless. This hardy strain is the only form of true cedar reliably hardy in Massachusetts.

Cercidiphyllum japonicum bO-lOO' Zone 4- Katsura Tree

\ wide spread injr tree with foliajre very much like that of Cercis canaden.sis usually ‘rrowinjr with several main stems or trunks. The flowers are insig'nificant, l)ut tlie small dry fruit capsules on the i)istillate trees the sexes are separate |

remain on the tree most of the winter. The rounded leaves are nearly 4 inches j long. Valued as a shade tree because of its wide-spreading habit but also valued I because of the rather loose foliage which allows for a great amount of air circu- ! lation. An excellent specimen tree of particular value for its graceful leaves which I remain unattacked by any insect pest throughout the entire season. Normally f wide-spreading in habit, it has been used as a substitute for Lombardy Poplar | (see Plate VI) when grown with a single trunk. |

Cercis canadensis alba 36' Zone 4 Eastern Redbud j

I

A common sight in the eastern United States, especially in the woods of Penn- j sylvania, Maryland, and Virginia when it blooms early in the spring is the Red- j bud. It is often planted with the Flowering Dogwood, blooming at the same time. The white flowered variety is almost as hardy as the species, and certainly ; worthy of wider use.

Eleagnus angustifolia 20' Zone 2 Russian Olive

The flowers and fruits of this plant are none too conspicuous, but the gray foliage is outstanding and the plant can be used for this one feature. Hardy and vigorous, it grows easily in many kinds of soils and its unique crooked trunk can easily be of interest in its own right for it is covered with a brown shredding bark | which is of considerable interest throughout the winter. j

Evodia danielli 2o' Zone .5 Korean Evodia

The Korean Evodia is fast becoming of interest because of its late summer flowers, at a time when few woody plants are in bloom. The flower clusters, nearly 6 inches across are made up of many small whitish flowers quite similar to the flowers of riburnum leiitago. This might be considered a ^^new” tree for the small garden, especially where late summer bloom and early fall fruits (red) are desirable. As a street tree it will not prove satisfactory for its wood is com- paratively weak and splits easily , and apparently is a short-lived tree ( 1 5-40 years).

Gleditsia triacanthos “Moraine” 100' Zone 4 Moraine Honey-locust 'Fhe thornless variety of the Hone,v-locust has been widely recommended as a substitute for the American Elm because it can be grown in so man}’ situations. The long twisted pods of the species are interesting for they remain on the tree ,

PLATE III

Kalopanax pictus is an excellent foliage tree, but as yet very rare in American gardens. Its fruits, in the late fall, are most attractive to birds.

lon^ after tlie leaves fall, yet under certain conditions can be troublesome since they must be raked off. It is not subject to borers as is the true Locust (Robinia), has no i)articularly interesting flowers nor autumn color. The new variety “Mo- ; raine,“ developed and patented by the Siebenthaler Nursery Company of Day- ton, Oliio, is thornless and is said to be sterile, hence no fruit pods are developed. ! 'riiis observation is based on the original tree which is over fifteen vears old and i

* It

1() inches in diameter. j:

Halesia monticola 90' Zone 5 Mountain Silverbell ||

Witli larger flowers than the Carolina Silverbell this species and its pink- flowered variety are planted more because they are more easily seen when in |i bloom. The pendant flowers, appear all along the twigs of the previous year’s | growth before the leaves appear making a well grown tree a unique and beautiful j sight when in bloom. At other times of the year, the tree is not meritorious but i it has no serious insect or disease pests, an important point to consider where [ annual maintenance and careful supervision will not be given. Because of its ' loose foliage, and comparatively small flowers, it might best be used where it can be closely observed, or else planted with an evergreen background of white pine ' or hemlock. |

Ilex pedunculosa 30' Zone 5 Longstalk Holly !i

This is one of the hardiest of evergreen hollies, and should be better known espe- | daily in northern gardens. The fruits are often as large as those of /. aquifolium. j

Kalopanax pictus 90' Zone 4 [

This tree should be grown much more than it is. Typically’ a tall, rounded | tree, its large maple-like leaves give it somewhat a tropical appearance, and a deep rich soil with plenty of moisture seems to be much the best for good growth. Some of the .vounger branches and vigorous shoots have sharp prickles, but most of these disappear at maturity. The small balls of flowers appearing in the late ^ summer are unique, and the small black fruits are quickly eaten by birds. Pos- I sibly the reason it is not grown more is because of the fact that the seeds take | two years to germinate and there are very few fruiting trees in this country, even j though it has been growing here for almost a century. A good shade tree devoid j of insect and disease pests it should be planted more widely. I

Koelreuteria paniculata 30' Zone 5 Golden-rain Tree

This and the Laburnum are the only trees with truly yellow blossoms that can , be grown in the Arnold Arboretum. It is quickly and easily grown from seed and i its large, upright and pyramidal, conspicuous flower clusters in early summer, fol- ! lowed by its equally conspicuous fruits, make it prominent throughout the sum- i mer period when most other trees have few if any flowers or colored fruits. It is |

being used a great deal in the Ohio Valley, even as a street tree. Because of its weak wood, this might be none too advisable. It has no autumn color and unless desired specifically for its summer bloom, other trees might be used instead which would have a longer life of ornamental usefulness. This much must be said in its behalf, however, it does seem to grow well in a wide range of soils.

Larix leptolepis 90' Zone 4 Japanese Larch

This is the best ornamental among the larches and seems to grow faster than some of the other species. However, it is not immune to the various troubles which plague most of the larch species, but it is less susceptible to canker disease than are the European and American Larch.

Magnolia denudata 45' Zone 5 Yulan Magnolia

Many people have learned to know this excellent tree under another name, M. conspicua, now superseded by the name denudata. It has been cultivated in the gardens of central China since the earliest times a splendid tree with large pure white conspicuous flowers in early May and should not be crowded by other plants but given plenty of room in which to develop. This means it should be allowed a ground space of about 30'.

Magnolia virginiana 60' Zone 5 Sweet Bay

The very fragrant, waxy white flowers appearing in June and early summer, the gray bark and good foliage with leaves white on the undersurface, make this an attractive native species. In the deep South this plant is a tree and nearly evergreen, but in New England it is much more shrubby and deciduous. It can be grown well in wet soils, although it does not require such situations to grow well an excellent native plant.

Malus “Dorothea” 25' Zone 4

This seedling was first noted in bloom when it was 5 feet high. The foliage resembles the Parkman Crab Apple somewhat, while the fruit resembles that of 3/. arnokliana. It is one of the very few semi-double flowered crab apples which also bear fruit, and particularly beautiful yellow fruit, ^ inch in diameter. Another very important characteristic is the fact that it bears double, slightly pinkish flowers annually, something which unfortunately cannot be claimed by all crab apples. Also it blooms early in life, young plants grafted one year frequently bloom the next.

Malus hupehensis 24' Zone 4 Tea Crab Apple

The Tea Crab Apple is the most picturesque of all crab apples because it is vase shaped in habit with long-reaching single branches growing from the trunk and spreading out like the ribs of a fan. In bud and flower, it is beautiful and its

PLATE IV

Top: The flowers of the Silverbell, Halesia monticola. Bottom: Flowers of the oriental cherry “Fugenzo” one of the few which can be planted in the warmer parts of Massa- chusetts.

marked habit is clearly evident every season of the year. The white flowers are produced on small spurs or short branches up and down the entire length of the long straight branches; the red fruits are small and not especially colorful.

Malus purpurea aldenhamensis 25' Zone 4 Aldenham Purple Crab Apple

Superior to the Purple Crab Apple because of a large number of petals (o-s), hence a longer period effective in flower. It frecjuently bears a few flowers a second and even a third time.

Malus purpurea lemoinei 25' Zone 4 Lemoine Purple Crab Apple

Lemoine’s Crab Apple has the darkest red flowers of any of the Malus species. It is decidedly ornamental, and is prominent anjwvhere. It is far superior to M. purpurea or M. pumila medz-icelshyana because of the darker colored flowers and also because they do not fade nearly as much.

Malus toringoides 25' Zone 5 Cutleaf Crab Apple

One of the last crab apples to bloom (late May) and one of the best in fruit the pear-shaped fruits being colored red and yellow remain on the plant in splen- did condition until after the first hard freeze. E. H. Wilson used to consider this the best of all species in fruit, but because its flowers are pure white it must be admitted that there are several superior to it for colorful flowers.

Oxydendrum arboreum 75' Zone 4 Sorrel Tree or Sourwood

This is one of the superior ornamental trees especially while it is young and can be kept clothed with branches from top to bottom and grown in a situation where it is exposed to full sunshine. Its leaves are similar in size and shape to those of Mountain-laurel; they are lustrous and effective throughout the growing season. The late summer flowers, brilliant scarlet autumn color and graceful py- ramidal habit give this tree additional interest every season of the year.

Parrotia persica 50' Zone 5 Persian Parrotia

An excellent tree for foliage, it usually grows with several trunks from the base and has leaves somewhat similar to those of the Witchhazel but more lus- trous. The flowers, appearing before the leaves, are insignificant, but the inter- esting bark flakes off in patches leaving a colorful trunk like that of the Stewartias or Finns hungeana giving it special interest in winter. Also the branches tend to be more or less horizontal and covered with leaves all in one plane. When allowed to grow with branches to the ground, older specimens can become very graceful indeed. This tree is not apparently infested with any serious insect or disease pest and might well be grown considerably more than it is.

PLATE V

Top: The southern Sourwood, Oxydendrum arhoreum. has flowers in late summer. Bottom: The Japanese Snowbell, Sty rax japonica, blooms in early June.

Phellodendron amurense 45' Zone 3 Amur Cork Tree

There has been some misunderstanding about the Phellodendron species, because C. S. Sargent states back in 1905 that P. sachalinense was best under cultivation. This statement has since been copied b.v many authors. The fact of the matter is that of the five species growing in the Arnold Arboretum P. amurense has been outstanding and C. S. Sargent has noted this in some of his writing in 1924. The other species are similar but P. amurense has the large branches of picturesque habit and corky bark which is of interest all winter. Like other species in this genus the sexes are separate and only pistillate plants will bear the numerous clusters of black berries. The autumn color is only of passing interest since the leaves quickly drop once they have turned yellow. It is a vigorous growing tree and easily and quickly grown from seed (seedlings are continually sprouting up all over the Arnold Arboretum more so than any other plant) and the roots are fibrous, making it easj’ to transplant. This wide-spreading tree produces only light shade and is of little interest in flower, but of particular interest in winter because of the massive branches and interesting bark.

Picea asperata 75' Zone 5 Dragon Spruce

Somewhat similar to the Norway Spruce in general appearance while young, this tree is finding a place for itself in seaside planting where it does better than most spruces. The needles of this species remain on the tree approximately seven years, the main reason why the foliage is so dense.

Picea omorika 90' Zone 4 Serbian Spruce

One of the best spruces for landscape planting. It has done very well indeed in the Arnold Arboretum since it was first introduced there seventy years ago. Its dense habit, and very beautiful glossy green needles, which show much of their whitish under-surfaces as they move in the wind, make it decidedly beauti- ful the entire year. Some of the trees have pendant branchlets which add ma- terially to its beauty. The Serbian Spruce can be termed almost columnar in habit, for old plants in the Arnold Arboretum 60 feet tall have a branch spread of no more than 15 feet at the base. If only one spruce is to be chosen for a planting this should certainly be considered first.

Pinus bungeana 75' Zone 4 Lace-bark Pine

A rather slow growing, dark green foliage tree, with excellent possibilities as a specimen plant because of its habit of growth and interesting bark. Very young plants will show the characteristic for exfoliating bark when the branches are only an inch in diameter. Also, this tree has the most desirable trait of holding its needles about five years, longer than most pines. Consequently this excellent specimen pine should be planted considerably more than it is. Its picturesque habit of growth with several major trunks, is also one of its desirable traits. ,

[ 1.5 ]

PLATE VI

Top: The Japanese Tree Lilac, Syringa amurensis japonica, blooms in mid-June. Bottom: The Katsura tree, Cercidiphyllum japonicum, when grown with a single trunk can be very columnar in habit (three trees on left). Grown with several trunks (two trees on right) it is very wide-spreading and rounded.

Pinus thunbergi

90'

Zone 4

Japanese Black Pine

The best pine, possibly the best evergreen, for planting along the seashore in the northeastern United States, is this Japanese Black Pine. It has done very well on Nantucket and Martha's Vineyard wliere other plants have failed, for it withstands salt laden winds right off the ocean remarkably well.

Prunus avium plena 00' Zone 3 Double Flowered Mazzard Cherry

This splendid tree has been in North America nearly To years but it is still not seen very often. Its beautiful double white flowers, nearly inches in diameter, appear in early May and are not borne profusely but they do remain effective for a very long time nearly a week longer than those of the single flowered Mazzard Cherry, which is of course widely planted for its fruits. All Mazzard cherries do best when grown in the full sun, for in the shade, only a very few flowers appear.

Prunus serrulata “Amanogawa” 20' Zone o

‘^Amanogawa” is the only truly fastigiate oriental cherry worth growing. Usually not over 20 feet tall, flowers l|^ inches semi-double, light pink and fra- grant. The varietal name means ^^milky waj *’ an indication of its floriferous blooms. David Fairchild is credited with first introducing this from Japan in 1906. It is interesting to note that a very high percentage of the seedlings of this tree are identical with the mother plant in form and flowers.

Prunus serrulata “Fugenzo” 20' Zone 5

This popular variety is also found in nursery catalogues under the name of “James H. Veitch’* and also “Kofugen.” The Japanese name translated means “goddess of a white elephant.” The flowers are as much as 2 2 inches in diame- ter, rosy pink fading to a light pink, double with about 30 petals, blooming at about the same time as “Kwanzan.” It is rather wide-spreading in habit.

Paul Russell in his excellent work on the “Oriental Flowering Cherries” notes that it was known to the Japanese 500 years ago and is still widely planted. It is often confused with “Shiro-fugen” but the flowers of this last variety fade.

Prunus serrulata “Kwanzan” 25' Zone 4

This is probably the most popular and the most hardy of all the double flow- ered oriental cherries. The deep pink double flowers are 2^ inches in diameter and have 30 petals. They are borne on a fairly upright growing tree about 12- 18 feet tall. The young foliage, as it first appears, is a bright reddish copper color, adding considerably to the colorful display of this tree in earl}’ spring. Probably the best display is at Washington, D.C., along the Tidal Basin where nearly 200 trees of this one variety alone are growing.

[ 17 ]

Pseuclolarix amabilis {kaempferi) 120' Zone o Golden Larch

'I'lie Golden [.arch is one of the most beautiful exotic trees. Oritrinally found by Robert Fortune ‘rrowinjr in pots for ornament in China and eleven years later lie found it •rrowing naturally in a monastery jrarden. Unfortunately it has never become pojiular in America, possibly because it is not a tree for the small garden, since trees even up to .30 and 40 feet are almost as broad as they are tall ! Also it is very likely that seed sources, especially in this country are very limited. Our trees have a good crop of seed only about every three or four years. On large estates or in parks, it can quickly become a beautiful specimen, interesting be- cause of its beautiful foliage throughout the spring and summer. In the late summer, when the cones begin to mature, these too are interesting and in the fall its beautiful golden yellow autumn color is very outstanding even though it is of sliort duration.

Sciadopitys verticillata 120' Zone 5 Umbrella Fine

'Fhis very beautiful tree, easily grown and not susceptible to any serious dis- f* ease, is valued for its dense habit and very dark evergreen foliage. Twenty to thirty' of the needles are arranged in whorls about the twigs somewhat similar to the ribs of an umbrella, from which similarity it gets its common name. These needles remain on the tree 2-3 years before falling off, and one of its good points is that it keeps its lower branches for a long time and so makes a splendid lawn specimen. Although growing tall in Japan, it is rather slow growing in this country and plants fifty years old in the Arnold Arboretum are still only 25 feet high. It should have good soil and not be planted in hot, dry situations.

Sophora japonica 75' Zone 4- Japanese Pagoda Tree

This is a good shade tree with alternate compound leaves a dark green color. The common name comes from the fact that it is frequently used around Buddhist temples in the Orient. It is also considerably used there as a wide-spreading street tree, with several desirable qualities. It blossoms in late summer, with large pyramidal clusters of yellowish pea-like flowers that are most conspicuous.

It is the last of the larger trees to bloom, and so is greatly desired as an orna- mental. One excellent quality is its apparent ability to withstand city condi- tions. Old trees have much the same general rounded habit as the White Ash. J'he yellowish pods, following the flowers, frequently remain on the tree all winter. A desirable large tree, it should be used considerably more than it is.

Stewartia koreana 45' Zone 5 Korean Stewartia

Smaller growing than S. pseudo-camellia but with larger flowers and just as in- teresting winter bark, this Korean Stewartia is very difficult to find in gardens. J'lie conspicuous early summer flowers that are pure white and 3 inches in diame- ter with golden centers, make it a useful small tree for bloom when few trees are

in flower. The habit is densely pyramidal. It is unfortunate that this excellent specimen is extremely difficult to find for it has been flourishing in the Arnold Arboretum where it is perfectly hardy, ever since 1 9 1 7 when it was first introduced .

The striking bark, irregularly flakes off in pieces, the older darker bark on the outside of the trunk breaking off to disclose the inner lighter colored bark be- neath it, somewhat similar to the bark of the Sycamore or Pinus hungeana.

Syringa amurensis japonica o(V Zone 4 Japanese Tree Lilac

This .Japanese Lilac can be grown as a tree with a single trunk and it is of special value because of the late bloom of the creamy white p3’ramidal flowers in mid-June. The shiny cherry-like bark is interesting in the winter, the large leaves and conspicuously vigorous habit is striking in the spring and summer, and the large creamy white pyramidal flower clusters, make it an outstanding plant, either as a specimen or in a group as screen or windbreak. The variety difl'ers from the species in being more tree-like in habit, taller and slightly later to flower. It is susceptible to borers and scale infestations which must be kept under control if it is to be a well grown plant, sufficient reason for not using it as a street tree where annual maintenance and close surveillance are necessities. This is the only native Japanese tree which F. L. Skinner can grow in the severe climate of Dropmore, Manitoba, Canada.

Thuja plicata ISO' Zone J Giant Arbor-vitae

This arbor-vitae is the best of the arbor-vitaes because its lustrous evergreen foliage does not turn brown in the winter as does the foliage of most of the T. occidentalis \aiY\ei\^s. Commercial growers in the northeastern United States have learned that it is necessary do use seed collected from plants high in the moun- tains of Montana and Utah, for i)lants grown from seed collected on the Pacific Coast have not proved hardy in the East. The Giant Arbor-vitae is a splendid tree, large or small, and can be kept restrained at almost any height by proper clipping.

Among the Best Common Trees

Abies concolor 1, 2, 3, 4, 5, 6, 7, 8, 10 Acer ginnala 2, 4, 6, 7, 9, 10

platanoides 1, 2, 3, 4, 5, 6, 7, 8, 9, 10

saccharum 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 Amelanchier canadensis 1, 2, 4, .7, 6, 7, 8 Betula lenta 4, 6

papyrifera 1, 3, 4, 6, 7, 8, 9 Cary a ovata 6, 10 Chamaecyparis obtusa 6, 7, 8, 10 Cladrastis lutea 1, 2, 3, 4, 5, 7, 8, 9

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Corn US riorida 1, *2, 8, 4, 5, d, 7, 8, 9, 10

kousa chinensis 2, 5, 6, 7, 8 Crataefifiis crusjfalli 1,2, 3, 4, 0, 7, 8

oxyacantha pauli 1, 2, 8, 4, .5, 6, 7, 8, 9, 10

phaenopyrum 1, 2, 4, 5, 6, 7, 8, 9

Fajjus species and varieties 1, 2, 4, 5, 6, 7, 8, 9, 10 Ginkfjo biloba 1, 2, 5, 6, 7, 8, 10 Ilex oj)aca 5, 6, 7, 8, 10 Juniperus virfjiniana 2, 4, 6, 7, 8, 10 Laburnum vossi 1, 2, 8, 4, o, 7, 8, 10 Liquidambar styraciflua 4, 5, 6, 7, 8, 10

Liriodendron tulipifera 1, 2, 4, 6, 7, 8, 9, 10

Majjnolia soulan^eana 1, 2, 3, 4, 5, 6, 7, 8, 9, 10

stellata 1, 2, 8, 5, 6, 7, 8, 9, 10

Malus arnoldiana 1, 2, 8, 5, 6, 7, 8, 9

atrosanguinea 1, 2, 8, 4, 5, 6, 7, 8, 9

“Eley” 1, 2, 3, 4, 5, 6, 7, 8, 9, 10

Horibunda 1, 2, 3, 4, 5, 6, 7, 8, 9, 10

“Hopa” 1, 2, 3, 4, 6, 7, 8, 9, 10

robusta 8, 4, 5, 6, 7, 8

scheideckeri 1, 3, 4, 5, 6, 7, 8, 9

zumi calocarpa 3, 4, 5, 6, 8, 10 N.vssa sylvatica 2, 4, 8

Picea glauca 1, 2, 3, 4, 6, 7, 8, 9, 10 Pinus resinosa 1, 2, 3, 4, 6, 7, 8, 9

strobus 1, 2, 3, 4, 6, 7, 8, 9, 10 Pinus sylvestris 3, 4, 6, 7, 8, 10 Primus sargenti 2, 4, 6, 8 Pseudotsuga taxifolia 1 , 2, 4, 6, 7, 8, 9 Quercus alba 4, 6, 7, 10

borealis 2, 3, 4, 7, 8

coccinea 3, 4, 7, 8, 9

palustris 1,2, 3, 4, 6, 7, 8, 9, 10 Sorbus aucuparia 1,2, 3, 4, 6, 7, 8, 9, 10 Styrax japonica 5, 6, 10

Tilia cordata 3, 4, 7, 8, 9, 10

platyphyllos pyramidalis 3, 7, 8

Tsuga canadensis 1, 2, 3, 4, o, 6, 7, 8, 9, 10

caroliniana 1, 4, 5, 6, 7, 8 Viburnum prunifolium 4, 6

Donald Wyman

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ARNOLDIA

Gray Herbarium

Harvard University

0.4, inri.

A continuation of the Rui.i.ktin ok Popular Information of the Arnold Arboretum, Harvard University

Volume MARCH ^1, 195^ Numbers 2-1

NUT GROWING IN THE NORTHEASJ'ERN STATES*

The Northeastern States have a rich heritage of native nut trees. Among the species occurring in the Helds and woodlands are six hickories, the black walnut, the butternut, two species of filberts, the beechnut, and formerly the chestnut. At the present time, however, the species have not been developed in the horticultural sense and so do not form any commercial industry, nor have they been improved by selection and breeding in a way comparable to the Per- sian walnut or the pecan. The nuts that are grown commercially in America such as the Persian walnut, the pecan, the European filbert, and the almond have all originated either in foreign countries or in the region to the South and West where the climate is better suited for their growth.

The planting of improved. nut trees in the northeastern states is thus a com- paratively recent development. To be sure nut trees have been given a sort of culture in that they have been left in the fence rows and in the fields that Mere cleared of other species, and seedling trees have been planted around the home grounds from which nuts have been harvested from time to time. Except with the chestnut it is only M’ithin the last quarter century that there has been any attempt to improve the nuts grown and to encourage nut culture in any real sense. Such improvements as have taken place have been the discovery of varie- ties that bear superior nuts and their propagation and testing. In the Northeast this process is still in the exploratory stage and there is yet much to learn as to the adaptation of the various kinds of nut trees to this region.

As the M'ork has progressed it has become evident that the successful produc- tion of improved nuts in the Northeast is largely dependent upon the discovery of varieties that are adapted to this region. Most ol‘ the varieties of nuts M’hich have been selected, named and propagated have originated to the South ami

* Referring specifically to New England, New York and Pennsylvania. Of course the in- formation would also apply to other regions with similar climate.

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W’est and when broii<rht into the northeastern states liave not produced good crops mostly because the climate is not warm enough and the growing season

long enough for the normal development of the variety. It seems obvious that for the most part in this region nut culture must be developed from varieties which have originated in the North or in parts of other countries which have a similar climate. The search for varieties adapted to the North has been going on for some time and a considerable number have been named. The time is now ripe for more extended planting of nut trees to determine their adaptability to growth in northern locations. Planting nut trees for shade and as a hobby is to be greatly encouraged because not only are trees of assured hardiness and landscape value available but the grower by testing varieties is contributing to our knowlege of nut culture in the Northeast.

Climatic Factors

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