=AMYGDALaCEAE.= The Plum Family.

Trees or shrubs with alternate, simple, petioled and usually serrate leaves; flowers perfect, calyx and corolla 5 numerous, stamens 15-30; fruit a 1-seeded drupe.

The characters which separate the species are not at all constant, and the species often vary much in the extremes of their range.

=PRuNUS.= The Plums and Cherries.

Flowers in umbel like cl.u.s.ters, or somewhat corymbose, appearing before or with the leaves on branchlets of the preceding year.

Margins of leaves with sharp teeth.

Petioles glabrous beneath 1 P. americana.

Petioles more or less p.u.b.escent all around. 2 P. americana var. lanata.

Margins of leaves with blunt or crenate teeth.

Teeth of center of leaves about 10 per cm.; calyx lobes glandular; fruit more than 10 mm. in diameter.

Princ.i.p.al leaves of fruiting branches generally more than 4 cm. broad; flowers white and generally more than 17 mm. wide. 3 P. nigra.

Princ.i.p.al leaves of fruiting branches generally less than 4 cm. broad; flowers white which on age show a tinge of pink and generally less than 17 mm. wide. 4 P. hortulana.

Teeth of center of leaves about 20 per cm.; calyx lobes glandless; fruit less than 10 mm. in diameter. 5 P. pennsylvanica.

Flowers in racemes, appearing after the leaves on twigs of the present year 6 P. serotina.

=1. Prunus americana= Marshall. Wild Red Plum. Plate 99. Small trees with crooked branches; bark of old trees exfoliating in irregular plates; twigs smooth; leaves obovate or oval, 5-9 cm. long, 2.5-5 cm.

wide, narrowed or sometimes rounded at the base, ac.u.minate at apex, margins sharply serrate or doubly serrate, glabrous above and smooth below, or hairy on the veins and sometimes more or less p.u.b.escent over the whole under surface, inner surface of petiole more or less hairy and sometimes bearing one or two glands; flowers appear in April or May before or with the leaves in cl.u.s.ters of 2-4 or sometimes singly, about 2 cm. in diameter, calyx smooth or with some hairs near the base of the lobes which are p.u.b.escent within and smooth or hairy without, lobes entire or cut-toothed above the middle, glandless or with inconspicuous glands; fruit ripens in August or September, usually globose, about 2 cm. in diameter, red; stone doubly convex, oval to nearly orbicular, surface usually smooth.

[Ill.u.s.tration: Plate 99.

PRUNUS AMERICANA Marshall. Wild Red Plum. ( 1/2.)]

=Distribution.=--Ma.s.sachusetts to Florida, west to Manitoba and south to New Mexico. Found throughout Indiana. While it has a general distribution, it is not generally distributed through the forests, but is local in colonies in low grounds along streams or in low places in the forest. In the southern counties it is found on the ridges and commonly about the basins of sink-holes. Large single trees may be found but they are usually surrounded by many smaller ones which are root shoots. From this habit of the tree to produce root shoots large colonies are formed which has given rise to the term "plum thickets."

=Remarks.=--The wood of this tree is of no economic importance, but the species from a horticultural standpoint is one of the most important of all of the plums. Many named varieties belong to this species.

It should be noted that all species of plums are quite variable, and one must not be surprised to find specimens that will not come entirely within the descriptions.

=2. Prunus americana= var. =lanata= Sudworth. Woolly-leaf Plum. Plate 100. Small trees with the characteristic wild plum tree bark, except on age it becomes more furrowed; twigs generally p.u.b.erulent or sometimes smooth; leaves obovate, oblong-obovate, or sometimes somewhat ovate, generally about 6-10 cm. long, and 4-6 cm. wide, rounded at the base, acute or short ac.u.minate at the apex, margins sharply serrate, or doubly serrate, upper surface covered with short appressed hairs, lower surface permanently p.u.b.escent with longer hairs; petioles more or less p.u.b.escent and often bearing one or more glands; flowers appear in April or May in umbels of 2-4, upper part of calyx, and its lobes p.u.b.escent both inside and out, the lobes more or less cut-toothed and bearing inconspicuous glands; fruit ripening in September, globose, reddish with a bluish bloom; stone nearly orbicular and turgid.

=Distribution.=--Indiana west to Indian Territory and south to the Gulf.

The range of this variety has not been well understood, and it is believed that forms of this variety in the northern part of its range have been included in the preceding species. It is certain that in our area the two forms are separated with difficulty; especially is this true of certain individuals. Specimens at hand show it to occur in Floyd, Clark, Bartholomew, Martin, Warren, Vermillion, Gibson, Warrick, and Perry Counties.

=Remarks.=--This form intergrades with the preceding to such an extent that there is little difference between the extremes of the two forms.

[Ill.u.s.tration: Plate 100.

PRUNUS AMERICANA variety LANATA Sudworth. Woolly-leaf Plum. ( 1/2.)]

[Ill.u.s.tration: Plate 101.

PRUNUS NIGRA Aiton. Canada Plum. ( 1/2.)]

=3. Prunus ngra= Aiton. Canada Plum. Plate 101. Small trees with the characteristic bark of the genus; twigs smooth; leaves obovate or oval, 5-11 cm. long and 3-6 cm. wide, rounded or somewhat narrowed at the base, abruptly short ac.u.minate toward the apex, smooth or spa.r.s.ely covered above with a short appressed p.u.b.escence, more or less p.u.b.escent beneath especially along the veins, usually p.u.b.escent on the veins at maturity, margins crenate-serrate, the teeth ending in persistent glands, petioles more or less p.u.b.escent on the inner surface, and generally bearing a pair of glands, which number varies from 1 to 3, or sometimes absent; flowers appear in April or May in umbels of 2-3, about 2 cm. in diameter--the largest of the genus in Indiana, calyx smooth, the lobes smooth without and within, except toward the base which is p.u.b.escent, the lobes reddish and the margins studded with numerous red glands; fruit ripens in July, globose, red; stone short oval and very flat.

=Distribution.=--New Brunswick to Ma.s.sachusetts and west to Minnesota and south to central Indiana. In Indiana it is definitely known only from Wells, Blackford and Marion Counties. No doubt it ranges throughout the northern part of Indiana, but it has not been separated from _Prunus americana_. Higley and Raddin[53] in 1891, when our text books did not separate this species, in a flora which included a part of Lake County Indiana, remark: "There are two distinct forms of _Prunus americana_; one with slender branches and large flowers with glandular calyx, found in swamps and another found with stout branches and much smaller flowers with the calyx less glandular, grows in dry soil." This no doubt refers to the species under discussion.

In 1898 the author found this species growing in a swamp in Wells County, and transplanted a specimen to high ground in his orchard. It has persisted ever since, growing vigorously and freely suckering from the roots, but it has been quite susceptible to the San Jose scale.

=4. Prunus hortulana= Bailey. Wild Goose Plum. Plate 102. Small trees with bark exfoliating in plates or rolls on old trees; twigs smooth; leaves oblong-oval, oval, slightly ovate or obovate, generally 6-11 cm.

long and 2.5-5.5 cm. wide, rounded and often slightly oblique at the base, ac.u.minate at the apex, margins finely serrated with short rounded and glandular teeth, generally glossy and smooth above, more or less p.u.b.escent all over beneath with long hairs, the midrib and lateral veins usually prominent below, petioles p.u.b.escent on the inner face and usually bearing one or more glands; flowers appear with the leaves in April or May in umbels of 2-4; calyx glabrous, the lobes glabrous on the outer face, and more or less p.u.b.escent within, margins glandular; fruit ripens in August, generally globose, red; stone generally short oval, very turgid, face reticulated.

[Ill.u.s.tration: Plate 102.

PRUNUS HORTULANA Bailey. Wild Goose Plum. ( 1/2.)]

=Distribution.=--Central Kentucky northwestward to central Iowa and southwestward to Kansas and east to northwest Tennessee. In Indiana the specimens at hand show it to be confined to the southwestern part of the State, although Pepoon[54] reports a single tree found near Dune Park in Porter County. It is found on sandy roadside cuts, base of sandy wooded slopes, etc., and is a common tree in Sullivan County for miles on the wooded bank of the terrace of the Wabash River.

=5. Prunus pennsylvanica= Linnaeus filius. Wild Red Cherry. Plate 103.

Small trees with smooth cherry-like bark, somewhat roughened near the base on old trees; twigs smooth, at least at maturity; leaves oval, oval-lanceolate, or ovate, sometimes slightly falcate, 4-10 cm. long, and 1.5-4 cm. wide, rounded or narrowed at the base, long ac.u.minate at the apex, margins finely serrate with glandular incurved teeth, glossy and smooth above, generally smooth beneath, sometimes p.u.b.escent along the midrib and veins, petioles generally smooth, rarely p.u.b.escent; flowers appear with the leaves in May in umbels of 3-7, or sometimes raceme-like but the rachis shorter than the pedicels; calyx glabrous, the lobes glabrous within and without, entire and glandless; fruit ripens in August, globose, 6-7 mm. in diameter, red; stone roundish-oval, surface granular.

=Distribution.=--Newfoundland and New England to the Rocky Mountains, south to Colorado and eastward through northern Indiana to Pennsylvania and thence in the mountains to North Carolina. In Indiana it is definitely known to occur only in Lake, Porter, Laporte, St. Joseph and Lagrange Counties. It is frequently found on the black oak ridges about Lake Michigan. All other reports of this species for Indiana should be looked upon with suspicion. The one by Chipman from Kosciusko County may be correct. The one by Ridgway[55] for Posey County is undoubtedly an error. No doubt Phinney's[56] record for Central Eastern Indiana (Jay, Delaware, Randolph and Wayne Counties) is an error.

The range of the species is to the north of our area, and like a few others it is found about the Great Lakes south of its general range. In Ohio it is reported only from Cuyahoga County which borders Lake Erie.

[Ill.u.s.tration: Plate 103.

PRUNUS PENNSYLVANICA Linnaeus fils. Wild Red Cherry. ( 1/2.)]

[Ill.u.s.tration: Plate 104.

PRUNUS SEROTINA Ehrhart. Wild Black Cherry. ( 1/2.)]

=6. Prunus serotina= Ehrhart. Wild Cherry. Cherry. =Wild Black Cherry.= Plate 104. Medium to large sized trees; bark of young trees smooth, becoming on old trees irregularly fissured and separating in small scaly plates; twigs slender and smooth, sometimes p.u.b.escent while young; leaves oval, oblong-oval, ovate or narrowly ovate, generally 5-12 cm.

long and 2-4 cm. wide, generally narrowed at the base, sometimes rounded, short or long ac.u.minate at the apex, margin finely serrate with incurved sharp callous teeth, smooth above and below, sometimes slightly p.u.b.escent beneath while young; flowers appear in May, when the leaves are almost grown, on the ends of the year's growth, in racemes generally 5-10 cm. long; fruit ripens in July and August, globose, about 6-10 mm.

in diameter, dark red to almost black.

=Distribution.=--Nova Scotia to South Dakota, south to Florida and west to Texas. Found in all parts of Indiana. It prefers a moist loose soil and is usually found with beech, sugar maple, tulip, white ash and white oak. In the original forest it was a rare to a frequent tree, and only rarely and locally did it ever become common. It grew to be several feet in diameter and was as tall as the highest trees of the forest. The trunk of the tree, however, was inclined to be crooked. It has now become a frequent tree along fences.

=Remarks.=--The wood of wild cherry from pioneer times has been a favorite wood, and for this reason the tree soon disappeared and today large trees are very rare. The wood is strong, close-grained, reddish-brown, and very much resembles mahogany. In value it stands second in Indiana woods. It is used princ.i.p.ally for furniture, office and store fixtures.

The wild cherry grows readily from seed; is not difficult to transplant; adapts itself to almost all kinds of soils and grows rapidly. In Spring it is one of the very first trees to put out its leaves. It is not shade enduring, which no doubt, in a great measure, accounts for its rarity in the primeval forests. When grown in the open the tree usually produces an abundance of fruit which is much relished by birds. This species has many good features, and might be used to advantage in forest planting.