Dwarf Sumac 605 



L THE SUMACS 



GENUS RHUS LINN^US 



JjBOUT 20 Sumacs are now known, natives of North America, Europe 

 and Asia. The type species is Rhus coriaria Linnaeus, of southern 

 Europe. Most of them are shrubs, but a few become small trees 

 under favorable conditions. They have alternate compound leaves 

 which turn red to crimson in autumn, either unequally pinnate with several or 

 numerous leaflets, or in some low shrubs of the genus the leaves are three-foliolate, 

 and in one southwestern form there is but one leaflet. The flowers are small, 

 green or rarely white, borne in panicles at the ends of branches, and open long 

 after the leaves appear, or in some shrubs in spike-like clustered racemes and 

 open before the leaves unfold; they are dioecious or mainly so; there are usually 

 5 sepals, and as maiiy petals and stamens; the stamens of the pistillate flowers 

 are very short and usually abortive, those of staminate flowers often as long as the 

 petals; the ovary in the pistillate flowers is ovoid, i-celled, and contains one 

 pendulous ovule; there are 3 styles, each with a knob-hke stigma. The fruits 

 are small drupes covered with acid hairs, the stone smooth, not ribbed, bony. 

 The North American Sumacs which form trees may be distinguished as follows: 



Rachis of the leaf wing-margined. 

 Leaflets ovate to oblong-lanceolate, acute. i. R. copalKna. 



Leaflets narrowly lanceolate, acuminate. 

 Leaflets falcate; Texan tree. 2. R. lanceolata. 



Leaflets not falcate; southern tree. 3. if. leucantha. 



Rachis of the leaf not wing-margined. 

 Twigs densely velvety. 4. R. hirta. 



Twigs smooth, or nearly so, usually glaucous. 5. R. glabra. 



I. DWARF SUMAC — Rhus copallina Linnaeus 

 ' Schmaltzia copallina Small 



While almost always a mere shrub seldom over 4 meters high, this species 

 occasionally becomes a tree 6 meters tall, with a trunk 1.5 dm. thick; it grows in 

 dry soil, preferring hillsides, and ranges from Maine to Florida, Ontario, Minne- 

 sota, Nebraska and Texas. Its sap is watery, not milky. 



The reddish brown bark is thick and scaly. The young twigs are finely vel- 

 vety, stou^. The very small buds are round and scarcely 2 mm. long. The 

 leaves are 3 dm. long or less, their stalks hairy and nearly round, the leaf-axis 

 between the 9 to 21 leaflets, wing-margined; the leaflets are rather thick, stalkless 

 or very short-stalked, ovate to oblong-lanceolate, entire-margined or few-toothed 

 toward the apex, pointed, dark green and smooth on the upper side, paler and 

 usually finely hairy on the imder, 2.5 to 7.5 cm. long. The flowers are in dense 



