Acer 



ACERACEAE 



657 



50 



Map 1367 



Acer saccharum Marsh. 



Jan. 



Feb. 



Mar. 



Apr. 



May 



June 



July 



Aug. 



Sept. 



Oct. 



Nov. 



Dec. 



Miles 



50 



Map 1368 

 Acer saccharum 

 f. Schneckii (Rehd.) Deam 



50 



Map 1369 



Aesculus glabra Willd. 



4c. Acer nigrum Michx. f. var. Palmeri Sarg. forma villdsum Deam, f. 

 nov. A forma typica recedit petiolis pubescentibus. Petioles more or less 

 pubescent their entire length. Associated with the variety but I do not 

 know its relative frequency. Type in Deam Herbarium no. 58437, Kos- 

 ciusko County, Sept. 19, 1937. 



5. Acer saccharum Marsh. Sugar Maple. Map 1367. A frequent to 

 common tree in all parts of the state. It is absent in the "flats" and on the 

 crests of the ridges in the unglaciated area. It is usually associated with 

 beech or in some of our northern woods the beech is replaced by basswood, 

 red oak, and white ash. The species is very variable in leaf outline and in 

 the pubescence of the petiole and the lower surface of the leaves. Several 

 forms based upon these characters have been named. The sugar maple in 

 Indiana has the lower surface of the leaves glaucous while in the northern 

 range of its distribution it has the lower surface of the leaves green. To 

 distinguish the two forms, Sargent (Bot. Gaz. 67: 233. 1919) named the 

 glaucous form var. glaucwn. 



Newf. to Man., southw. to Ga. and Tex. 



5a. Acer saccharum Marsh, forma Schneckii (Render) Deam, comb, 

 nov. (Acer saccharum var. Schneckii Render and Sargent, Trees and Shrubs 

 2 : 256. 1913.) Map 1368. This is a form found with the species and is re- 

 stricted to a few of the southwestern counties. The few trees I have seen 

 usually have a decidedly whiter bark and the trunk and branches have a 

 more gnarled and twisted appearance. I have had it under cultivation since 

 1919 and seed from this tree shows that the seedlings do not come true (all 

 with pubescent petioles) . 



Wis., Ind., 111., Mo., w. Ky., and w. Tenn. 



5b. Acer saccharum var. Rugelii (Pax) Render. This is a form with 

 3-lobed leaves that is infrequent throughout our area. 



