432 



Minnesota Plant Diseases 



Willow, 



powdery mildew of (Fig. 



52), 125, 126 



rusts, 160 



tar spots (Fig. 133), 142, 270 



Wilt of cucurbits (Fig. 173), 341 

 of flax (Figs. 156, 157, 158, 

 159), 3io to 314 



Wind, assistance in infection, 98 

 spore distribution in puff- 

 balls, 182 



Wine, bacteria in, 196 



Witches'-broom (Fig. 22), 51, 52 

 age of mycelium, 20 



caused by insects, 56 



caused by leaf curl fungi, 121 

 of rust origin, 164 



on balsam fir (Fig. 



23), 153, 277, 278 



on birch, 56, 271 



on cherry, 56, 363 



on red cedar (Figs. 26, 



57), 54, 55 



on spruce (Fig. 101), 199,200 

 on white spruce (Figs. 24, 



25, 55), 54 



stunting in age, 82 



Witches' butter, a trembling 



fungus, 169 



Wood, attacked by fungi, 40 



basidium bearing fungi on, 154 

 bird's-nest fungi on, 186 



characters of, 85 



dead, cup fungi on, 142 



-destroying fungi, action on 



lignin (Fig. 38), 85,86 



-dwelling fungi, action on 



wood, 40 



-dwelling fungi, methods of 



entrance, 40 



-dwelling fungi, nutrition, 40 

 -dwelling habit, 40 



gill fungi on, 179 



Jew's-ear fungi on, 166 



palisade fungi on, 171 



-peckers, agents of spore 



distribution, 31 



-peckers, wounds caused by, 47 

 rot, coral fungus (Fig. 119), 



244, 246 

 rot, destruction of wood 



(Fig. 38), 86 



Wood, 



rot, creeping pore fungus, 258 



rot, partridge (Fig. 118), 242 

 rot (see also timber rots), 



rot, Stereum (Fig. 117), 240 



sphere throwing fungi on, 184 



tissues. 85 



tooth fungi on, 175 



trembling fungi on, 167 



Worms, degeneration in, 10 



true, parasites of, 67 



Wound infection and prevention 

 of disease, 204, 205 



parasites (Fig. 20), 



45, 46, 80, 235 



parasites, birch fungus, 255 

 parasites, degree of para- 

 sites, 58 

 parasites, destroyers of 



branches, 80 

 parasites, false tinder fun- 

 gus, 250 

 parasites, gill fungi, 179 

 parasites, ring scale of pine, 256 

 parasites, scaly pore fungus, 254 

 parasites, Stereum (Fig. 



117), 241 



parasites, sulphur fungus, 253 



parasites, tinder fungus, 251 



Wounds, cause of, 47 



causes of predisposition, 96 



in bark, entrance of rots, 41 



in bark, causes, 41 



Yeast-like fungi on animals, 66 



on man, 75 



on water flea, 67 



Yeasts (Fig. 48), 118, 119, 120 



allies of, 120 



fermentation, 36 



habit of saprophytes. 36 



in bread making, 119 



in slime exudation, 120 



in slime flux, 271 



occurrence in nature, 36 



power of fermentation, 119 



Yellow piped oak, 240 



Youth, predisposition of, 95 



relation to disease, 9 1 



Zinc chloride, to prevent tim- 

 ber rot, 239 



Zoned Polyporus rot, 258 



Zoogloea, 190 



