ent - 
1906] WIEGAND—BUDS AND TWIGS IN WINTER 21 
4 
sified by the comparative rigidity of the twig to which the buds 
are attached. Danger to buds from mechanical causes during 
the winter may be classified under three heads: danger from birds, 
from passing objects, and from wind. 
Birds—Young and tender plant tissue is a favorite food for 
some birds, as for instance the purple finch.s? It is quite possible 
that if the bud-scales were absent from our native trees, many species 
of birds would take advantage of this easy method of obtaining 
food, at a time when food is scarce. More birds might remain 
in the North than now, so that altogether it seems probable that 
trees would suffer severely, if they were not actually killed, by the 
depredations. A firm hard armor is therefore desirable. 
Passing objects—During my experiments with buds from which 
the scales had been removed to determine the effect of evaporation, 
€etc., many buds were prepared in a thicket of lilac bushes about 
six feet high. I found great difficulty in passing through to inspect 
the buds without breaking off some of them. A moment’s*absent- 
mindedness while taking notes would frequently result in the de- 
struction of several buds, a very slight touch only being necessary 
to dislodge the tender shoot, and the brittleness was of course very 
much increased when the tissues were frozen. If the above results 
occurred when care was observed in passing, how much greater 
would be the damage caused by animals both large and small run- 
ning thorugh the dense copses in winter. Protective armor seems 
here again to be a necessity. 
Wind—In our American climate, at least, this is much stronger 
in winter than in summer—in other words, at exactly the time when 
buds are frozen and therefore most brittle. The beating together 
of branches during a heavy wind storm could scarcely fail to do 
incalculable damage to a tree with unprotected buds. ScCHUMANN*$ 
believed that one of the most, if not the most, important functions 
of bud-scales is to resist injury from heavy winds. I myself was 
32 Forsusn, E. fe Birds and woodlands. Mass. State Board of Agric. Rep. 
1900:300. Brat, F. E. L., How birds affect the orchard. Year Book Dept. of 
Agric. 1900: 2 291. Attu, Zerstérung von Baum- besonders Fichten- und Kiefern- 
knospen durch Végel. Zeitschr. Forst. u. Jagdu. 29: 224-230. 1897. 
33 SCHUMANN, C. R. G., Anatomische Studien iiber die Knospenschuppen von 
3 
Coniferen und dicotylen Holzgewichsen. Biblioth. Botan. 15:23. Cassel. 1889. 
