6 



MASS. EXPERIMENT STATION BULLETIN 413 



Elephant Heart through the light green of Early Laxton, the green of Abundance, 

 and the reddish tinge of Beauty to the dull red of Under\\ood and the bright red 

 of Pearl. Varieties also diflfer in the color of the young leaves a little back from the 

 tip although this character is neither so significant nor so characteristic as the 

 color of the tips. However, the color may range from very light yellowish green 

 in Elephant Heart through light green in De Montfort to rather dark green in 

 Glass. Sometimes these leaves are more or less characteristically bronzed as in 

 Pipestone. 



Figure 2. Shoct Pubescence. (2 X ) 

 1. LOMBARD none, 2. FIELD — medium: 3. MONARCH 



heavy. 



The petiole is fairly important as a distinguishing varietal character in plums. 

 The angle that the petiole makes with an upright shoot is usually wide, i. e., 

 approaching a right angle. However, in some varieties the petioles are often 

 medium-angled as in Formosa or occasionally moderately narrow-angled as in 

 Elliot. Usualh' the Japanese plums have more nearly upright leaves than the 

 European. Petioles are usually straight but sometimes are upcurving as in 

 American Mirabelie. They may also vary in length, thickness, and color. A 

 petiole may be typically short and thick as in Washington, short and slender 

 as in Imperial Epineuse, or rather long as in Monitor. Its color varies from 

 essentially green as in Glass, through reddish tinged as in Imperial Gage and 

 reddish as in Gueii, to red as in Field. Color is not a constant character, being 

 influenced by vigor, age, and environment. However, with these limitations 

 kept in mind, petiole coloration can be \'ery useful in assisting in the identifica- 

 tion of some varieties. 



