196 



ACER 



ACER 



seeds, which soon lose their germinating power and 

 must be sown soon after maturity or stratified and 

 sown in spring; A. aaccharum and A. Negundo keep 

 their germinating power somewhat longer. The early- 

 ripening species, like A. saccharinum and A. rubrum, 



must be sown 

 as soon as they 

 are ripe and 

 they will germi- 

 nate the same 

 year. A . cam- 

 pestre, A. mons- 

 pessulanum and 

 other species of 

 this group do 



*<\fi(?!H.S'/"'J* ; ?~~ - not usually ger- 

 minate until the 

 second year. 

 The varieties 

 and rare species 

 may be budded 

 in summer on 

 the typical 

 forms or on spe- 

 cies of the same 

 group; kinds be- 

 longing to differ- 

 ent groups can- 

 not, as a rule, be 

 grafted on each 

 other; e.g., va- 

 rieties of A. platanoides will not grow on A. pseudo- 

 platanus and vice versa, but A. insigne will grow on 

 A. pseudoplatanus, as they belong to the same group. 

 Some shrubby species, as A. palmatum, also A. cissi- 

 folium, A. ginnala var. Semenowi, and A. Ixtum var. 

 rubrum, may be propagated by layers or half-ripened 

 greenwood cuttings in summer, or, still better, by 

 cuttings taken from forced plants in early spring in 

 the greenhouse. A. Negundo grows also from hard- 

 wood cuttings. Fancy maples are readily winter-grafted 

 by the veneer method, the stocks being grown in pots. 

 The Japanese kinds are usually worked on imported 

 stocks of A. palmatum. 



INDEX, CONTINUED 



89. A pasture maple in autumn, showing 

 the strong framework. 



INDEX. 



13, 



albo-limbatum, 32, atropurpureum, 

 albo-variegatum, 5, 22. 



22, 36. auratum, 49. 



argenteo-variegatum, aweo-maculatum, 49. 



2, 24, 49. aureo-marginatum, 

 argutum, 35. 5, 49. 



atrolineare, 13. aureo-variegatum, 49. 



90. Pasture tree of Acer saccharum, sugar 

 maple. Tree flatter-topped than usual. 



aureum, 8, 13, 15. 

 austriacum, 2. 

 barbatum, 38, 39. 

 betulifolium, 34. 

 bicolor, 13, 22. 

 californicum, 49. 

 campestre, 2. 

 cappadocicum, 8. 

 carpinifolium, 27. 

 catalpifolium, 10. 

 caudatum, 20. 

 circmatum, 12. 

 cissifplium, 48. 

 colchicum, 8. 

 columnare, 5, 37 

 concolor, 26. 

 cratsegi folium, 30. 

 crispum, 13, 36, 49. 

 cucullatum, 5. 

 dasycarpum, 36. 

 Davidii, 28. 

 diabolicum, 43. 

 discolor, 26. 

 dissectum, 5, 13. 

 Douglasii, 11. 

 Drummondii, 5, 37. 

 elobulatum, 34. 

 eriocarpum, 36. 

 erosum, 20. 

 erythrocarpum, 22. 

 erythrocladum, 33. 

 filicifolium, 15. 

 floridanum, 39. 

 Frederici-Guilelmi, 13. 

 Geneva, 5. 

 ginnala, 18. 

 glabrum, 11. 

 globosum, 5, 37. 

 grandidentatum, 42. 

 griseum, 45. 



KEY TO THE SPECIES. 



A. Lvs. simple, mostly palmately lobed 



(occasionally S-foliolate in No. 11). 

 B. Sepals and petals distinct (petah 



wanting in Nos. 27 and SB) . 

 c. Fls. appearing with or after the Ivs. 

 in corymbs, panicles, or racemes. 

 D. Arrangement of infi. corymbose 

 (broadly paniculate in No. 4)- 

 E. Winter-buds with several im- 

 bricate scales: lobes entire or 

 coarsely toothed, rarely hs. 

 without lobes. 

 r. Lobes obtuse or bluntly 



pointed. 



o. Lvs. 1-3% in. across, 

 usually 3-lobed; lobes 

 usually entire or with 

 few teeth. 



H. Corymbs glabrous: lobes 

 entire, Ivs. glaucous 



beneath 1. monspessu- 



HH. Corymbs pubescent, up- [lanum 

 right: lobes usually 

 dentate, hs. green be- 

 neath 2. campestre 



GO. Lvs. 3-6 in. across, 3-5- 



lobed; lobes toothed. 

 n. Inf.. corymbose, many- 

 fld. pendulous: Ivs. 

 glaucescent beneath; 

 lobes obtuse or acute .. 3. Opalus 

 HH. Inf.. paniculate, up- 

 right: Ivs. green be- 

 neath and pubescent: 

 lobes obtusely acu- 

 minate 4. Miyabei 



IT. Lobes acuminate, finely 



pointed: corymbs glabrous. 



o. Lvs. glabrous beneath, 



6-7-, rarely 3-lobed: 



corymbs stalked. 



n.Bark of mature 



branches ashy gray or 



light grayish brown, 



slightly fissured and 



marked with lenticels. 



I. The lobes coarsely 



toothed 5. platanoides 



n. The lobes entire or 

 rarely with few teeth. 



