40 OUR SHADE TREES AND THEIR INSECT DEFOLIATORS. 
hatched upon them, but as the migrating swarm became pressed with 
hunger they finally fell upon these, and even upon plants like the Peach, 
and Ailanthus, which ordinarily are passed over. Tbey would pounce 
upon any food, and a rotten apple placed in their way was soon literally 
swarming with them and sucked dry. 
“In a general way it may be stated that conifers, grapes, and most 
herbaceous plants are free from their attacks, and it is very doubtful 
whether the species can mature upon them. 
“The list of plants which follows is arranged according to the relative 
damage to the foliage in the city of Washington. The three first named 
are most subject to attack, and, in fact, are almost always defoliated. 
PROPORTIONATE INJURY TO DIFFERENT PLANTS AND SHADE TREES. 
‘“‘The damage done in the city of Washington was exceptional, but 
so was also the general damage throughout the New England States, if 
not throughout the country. In New England the greater predilection 
which the species showed for Poplar, Cottonwood, and the ranker grow- 
ing Willows was every where manifest, and so much was this the case that 
the destruction of the first brood on these trees would have substan- 
tially lessened the damage to other trees.” 
Plants marked 1 have lost from 75 to 100 per cent. of their foliage. 
Plants marked 2 have lost from 50 to 75 per cent. of. their foliage. 
Plants marked 3 have lost from 25 to 50 per cent. of their foliage. 
Plants marked 4 have lost from 0 to 25 per cent. of their foliage. 
Plants marked with two figures have shown the relative immunity or 
injury indicated by both, the variation being in individual trees. 
1. Negundo aceroides Mench. (Box El- 2. Tilia americana L. (American Lin- 
der. ) den. ) 
1. Populus alba L. (European White 2. Tilia europea L. (European Lin- 
Poplar.) | den. ) 
1. Populus monilifera Aiton. (Cotton- | 2. Populus dilatata Ait. (Lombardy 
wood.) | Poplar. ) 
1-2. Populus balsamifera L. (Balsam 2. Ulmus americana L. (American 
Poplar.) White Elm.) ' 
1-2. Populus tremuloides Mich’x. (Amer- 2-3. Ulmus fulva Mich. (Slippery Elm.) 
can Aspen.) | 2-3. Prunus armeniaca L. (Apricot.) 
1-2. Fraxinus americanaL. (White Ash.) | 2-3. Alnus maritima Muhl. (Alder.) 
1-2, Fraxinus excelsior L. (European | 2-3. Betula alba, L. (White Birch.) 
Ash.) 2-3. Viburnum species. (Haw or Sloe.) 
1-2. Sambucus canadensis L. (Elder.) | 2-3. Lonicera species. (Honeysuckles. ) 
1-2. Pyrusspecies. (Cultivated Pearand | 2-3. Prunus americana Marsh. (Wild Red 
Apple.) Plum.) 
1-2. Prunus avium and cerasus L. (Cher- | 2-3. Celtis occidentalis L. (Hackberry. ) 
ries. ) 2-3. Rosa species. (Rose.) 
1-4. Syringa vulgaris L. (Lilac.) 2-3. Gossypium album Ham. (Cotton.) 
1-4. Ilex spec. (Holly.) 2-3. Cephalanthus occidentalis L. (Button 
2. Platanus occidentalis L. (Sycamore.) | Bush. ) 
2. Salix species. (Willow.) 2-4. Convolvulus spec. (Morning Glory.) 
