=CAESALPINaCEAE.= The Senna Family.

Leaves simple; flowers pink; seed pod papery 1 Cercis.

Leaves compound; flowers not pink; seed pod woody or leathery.

Trees with thorns; stamens 3-5, longer than the corolla; pods flat and leathery; seeds about 1 cm.

(1/2 inch) long 2 Gleditsia.

Trees without thorns; stamens 10, shorter than the corolla; pods swollen, woody; seeds about 2 cm.

(1 inch) long 3 Gymnocladus.

=1. CeRCIS.= The Redbud.

=Cercis canadensis= Linnaeus. Redbud. Plate 105. Small trees; bark of trunk of old trees fissured, reddish-brown; twigs glabrous, light brown, becoming a dark brown; leaves alternate, broadly ovate, average blades 6-14 cm. long, cordate at base, short-pointed, sometimes short-ac.u.minate or rarely rounded at the apex, margins entire, glabrous or p.u.b.escent on unfolding, at maturity usually glabrous on both sides, or with a few hairs in the axils of the veins or along the veins, sometimes more or less p.u.b.escent beneath, and with hairs on the veins above; petioles generally 2-6 cm. long; flowers appear in April or May before the leaves, in cl.u.s.ters of 4-8 on the branches of the preceding season, pink or rose color; pods 5-10 cm. long, thin, flat and glabrous; wood heavy, hard and weak.

=Distribution.=--In Canada along the sh.o.r.es of Lake Erie and Ontario, New York west through Michigan to Iowa, south to the Gulf States and west to Texas. Found throughout Indiana except there are no records from the counties bordering Lake Michigan. In the northern part of the State it is rare or frequent in alluvial soil along streams or in rich woods.

In the southern part of the State it is a frequent to a common tree in ravines and on slopes. It is never found in wet situations, and consequently is absent in the "flats" of the southern counties.

=Remarks.=--The redbud is the common name for this tree throughout the State. In one locality it was known as the fish blossom because the larger fish sp.a.w.n when this tree is in flower. In text books it is also called Judas tree. It is usually a tree 1-1.5 dm. in diameter and 5-10 m. high. It is of no economic importance and is cla.s.sed as a weed tree in the woodlot and should be removed.

It is frequently recommended for ornamental planting. It prefers a rich moist soil, and is shade enduring, although it succeeds best in the open or in a light shade.

=2. GLEDiTSIA.= The Honey Locust.

Pods more than 8 cm. long; seeds oval 1 G. triacanthos.

Pods less than 8 cm. long; seeds...o...b..cular 2 G. aquatica.

=1. Gleditsia triacanthos= Linnaeus. Honey Locust. Plate 106. Medium to large sized trees; bark of old trunks fissured and peeling off in strips; spines on trunk large and often much branched, sometimes 4 dm.

long; spines on branches not so large, generally more or less forked; twigs at first green, turning a light brown; leaves pinnate or bipinnate, 1-2 dm. long, rachis permanently p.u.b.escent; leaflets 9-14 pairs, fewer on the bipinnate forms, petiolules about 1 mm. long, form variable from ovate to lanceolate, sometimes somewhat falcate, generally 2-3 cm. long, usually more or less p.u.b.escent beneath; flowers appear in May or June, inconspicuous, greenish-yellow, rich in honey, their appearance being announced by the hum of the swarm of insects visiting them; fruit a flat, linear twisted pod, 2-4 dm. long, glabrous and l.u.s.trous or p.u.b.escent on the sides; seeds several, oval, about 6 mm.

wide, and 10 mm. long, glabrous and chestnut brown; wood heavy, hard, strong, coa.r.s.e-grained and takes a good polish.

[Ill.u.s.tration: Plate 105.

CERCIS CANADENSIS Linnaeus. Redbud. ( 1/2.)]

[Ill.u.s.tration: Plate 106.

GLEDITSIA TRIACANTHOS Linnaeus. Honey Locust. ( 1/2.)]

=Distribution.=--Pennsylvania, southern Michigan to Iowa, and south to the Gulf States and west to Texas. Found infrequently throughout Indiana along streams, except that it is absent about Lake Michigan and that in the southwestern counties it becomes a frequent tree in the Wabash bottoms. In its native habitat it is rarely found except near a stream, pond, lake, etc. However, in the southeastern counties it has spread all over many of the hillsides which were once cleared and have been abandoned for agricultural purposes and left to natural forest regeneration. It was interesting to learn how this tree was able to propagate itself on the steep bare slopes. It was found that the seeds were scattered by cattle that greedily eat the fruit. It is a medium sized tree, except in the Wabash bottoms of the southwestern part of the State where it grows to be one of the largest trees of the forest, and is more luxuriant than in any other part of its range.

=Remarks.=--In making a study of the fruit of this species, it was found that the sides of all the pods of all the specimens at hand except one are glabrous, even those of young fruit. The margins of the pods are p.u.b.escent. However, a specimen collected on August 27th in Vermillion County has the entire pod covered with long hairs. In consulting the literature on the subject it is found that some authors describe the fruit as glabrous while others describe it as hairy. It would be interesting to study the significance of this character to learn if each form has a geographic range.

The wood is used princ.i.p.ally for interior finish, furniture, posts and crossties. The tree has a grace that recommends it for ornamental planting despite its thorns. However, a thornless variety is now offered by nurserymen. It adapts itself to all kinds of soils, although it prefers a moist rich soil; grows rapidly and is comparatively free from insect damage.

[Ill.u.s.tration: Plate 107.

GLEDITSIA AQUATICA Marshall. Water Honey Locust. ( 1/2.)]

=2. Gleditsia aquatica= Marshall. Water Honey Locust. Plate 107. A medium sized tree with rather smooth bark, which becomes rough and flaky on large trees; twigs greenish, turning to a light brown by the end of the year; branchlets a greenish-gray brown; spines all usually more or less flattened, those of the branchlets and branches, rather few and usually simple, 4-10 cm. long, those of the trunk branched, spines do not develop on the year's growth; leaves from old wood pinnate, from the year's growth bipinnate; rachis grooved and p.u.b.escent or p.u.b.erulent above and smooth below; leaflets generally 7-11 pairs, variable in shape and size, generally lanceolate and 1.5-2.5 cm. long, on petiolules about 1 mm. long, glabrous; flowers similar to the preceding species; fruit a glabrous, shining, oblique pod about 4-5 cm. long, containing 1 seed; seeds...o...b..cular, flat, chestnut brown, about 1 cm. in diameter.

=Distribution.=--Atlantic Coast from North Carolina south to Florida, and the Mississippi Valley from southwestern Indiana southward to Texas.

In Indiana this species is rare and limited to the banks of river sloughs, locally called ponds and to one cypress swamp. It is known to have occurred on the banks of Wabash and Dan's ponds and Little Cypress swamp in the southwest corner of Knox County, and in Gibson County on the bank of a slough near Skelton and about Burnett's pond. The reference to Posey County is without a verifying specimen, although it may be found in the county. The writer has visited about every place in the county where the species might occur, and has never found it.

Gorby's[57] reference for Miami County is without doubt an error. In our area it is a low crooked tree and grows with its base submerged more or less during the year. The idea of the proportions of this tree can be obtained from the measurements taken from the largest tree now known in Indiana, which is located on the sh.o.r.e of Dan's pond in Knox County. It measures 158 cm. (66 inches) in circ.u.mference at 1 m. above the ground, and is estimated to be 10 m. (30 feet) high. This species is too rare to be of economic importance.

=Gleditsia aquatica triacanthos.= Dr. Schneck[58] found two honey locust trees which he described as hybrids of the two species. The one was located on the bank of Dan's pond in Knox County, and the other in Gibson County. The original description is as follows: "In both instances the pods are the distinguishing feature. These are very much alike in both trees, being about 5 inches long, 1-1/2 inches wide, smooth, shining, of a light brown color and entirely dest.i.tute of pulp.

Otherwise the tree cannot be distinguished from the trees among which they stand. They are both about 50 feet high, with short stems and spreading branches, and stand about 5 miles apart." The writer has five fruiting specimens from these two trees, taken by Dr. Schneck. Two of the sheets have the round and branched spines of _G. triacanthos_.

=3. GYMNoCLADUS.= The Coffee Tree.

=Gymnocladus dioica= (Linnaeus) Koch. Coffeenut Tree. Plate 108. Medium sized trees; bark of trunks fissured, the ridges often curling up along the sides, very hard; twigs at first hairy, becoming glabrous and mottled gray-brown by the end of the season, robust, usually about 1 cm.

in diameter; leaves alternate, twice pinnate, 3-9 dm. long, leaflets usually 6-10 pairs, ovate, generally from 3-4 cm. long, generally oblique and rounded, wedge-shape or truncate at the base, acute or very sharp-pointed at the apex, petiolules about 1 mm. long, p.u.b.escent on both sides at first, becoming glabrous or nearly so at maturity; flowers of two kinds, the male and female on separate trees, appearing in May or June; fruit a pod generally about 1-2 dm. long, thick, curved; seeds generally 4-7, large, flattened about 2 cm. in diameter; wood heavy, not hard, coa.r.s.e-grained and takes a high polish.

=Distribution.=--New York, southwestern Ontario to southern Minnesota south to Tennessee and Arkansas. This species has been reported or is known to exist in 33 counties in various parts of the State. It no doubt was native to every county of the State, except it be those bordering Lake Michigan from which we have no reports. It is a rare tree in all parts. Only exceptionally is it found even frequently. A few trees may be found in one place, and it will not be found again for many miles. No doubt there are many areas with a radius of 5 to 10 miles where this tree never occurred. It is usually found in alluvial soil along streams, or nearby terraces.

=Remarks.=--This species generally is not very tall, and is usually found in open places in the forest or cut-over lands. However, one specimen was seen in Posey County that was as tall as a specimen of pecan of equal size that grew nearby. This species was so rare in this vicinity that I was asked to drive three miles to identify this tree which no one could name.

Coffeenut, which is sometimes called Kentucky coffeenut, has always been so rare as to be of little economic importance. It has no qualities to recommend it for ornamental planting.

=FABaCEAE.= The Pea Family.

Trees, shrubs, vines or herbs with alternate leaves, mostly compound; flowers with five petals which are pea-like (papilionaceous); stamens generally 10; fruit a legume.

[Ill.u.s.tration: Plate 108.

GYMNOCLADUS DIOICA (Linnaeus) Koch. Coffeenut Tree. ( 9/20).]

=ROBiNIA.= The Locusts.

=Robinia Pseudo-Acacia= Linnaeus. Locust. Black Locust. Plate 109. Medium sized trees with deeply furrowed bark; twigs at first green and hairy, becoming at the end of the season glabrous and a light brown, the stipules developing in about a year into a pair of woody spines about 2 cm. long; leaves pinnate, 1.5-3 dm. long; leaflets 7-17 on short stalks, ovate to oblong, 2-6 cm. long, rounded at base, rounded or pointed and with a small indenture at apex, margin entire, p.u.b.escent on both sides at first, becoming at maturity glabrous above and remaining more or less p.u.b.escent below, especially on the midrib; flowers in loose racemes, white, expanding in May or June; fruit a flat and slightly curved pod about 5-10 cm. long, glabrous; seeds usually 4-8 in each pod, about 4 mm. long and 2.5 mm. wide; wood heavy, very hard, close-grained, takes a good polish, very durable in contact with the soil.

=Distribution.=--Appalachian Mountains from Pennsylvania south to northern Georgia, and in Arkansas. In Indiana it is found as an escape in all parts and was doubtless native along the Ohio River, at least in the southeastern part of the State. Thomas[59] says: "We had gazed at the majestic beech of this country (near Rising Sun) three feet in diameter; we had seen the honey locust, the black walnut, a buckeye of equal magnitude; and then we saw with surprise, the black locust almost a rival in stature." Drake[60] says: "The flowering locust is abundant in Kentucky. Along the Ohio River it is rarely found more than 30 miles north of the river."

=Remarks.=--This tree is generally known as the locust tree, but is sometimes called the yellow locust.