125 



from New York and California, and in both cases waa reported to infest Coleus. lu 

 the same line of your experiment with fir-tree oil would be the application of the 

 kerosene emulsion, which will doubtless be as effective as the former treatment and 

 less expensive. If you are not already acquainted with the method of making thii^ 

 emulsion, the accompanying formula will give ample directions. — [June 23, 1890.] 



The Cottony Maple Scale in Oregon. 



I send you to-day under another cover a specimen of a Scale or Bark Louse that is 

 infesting some of our trees here. The specimen sent is taken from the soft maple. 

 I am inclined to think that it is the Maple Scale; but its appearance and habits 

 answer completely those given of the Cottony Cushion Scale, anddo not answer those 

 given of the Maple Scale. The color of the eggs of these are pinkish, and I have never 

 found them on the leaf, but always upon the stem or limb of the tree. They infest 

 the Maple, Box Elder, Locust, Pyracanthus, and in fact nearly everything in the way 

 of tree or shrub. I have thus far not been able to discover any serious eli'ect upon 

 the tree or shrub from their workings. Please advise me wliat they are, and 

 oblige. — [E. W. Allen, Secretary Oregon State Board of Horticulture, Portland, Ore- 

 gon, July 16, 1890. 



Reply. — The insect which you send, and which is damaging your soft Maple shade 

 trees, is the common Cottony Maple Scale of the East (Pulvinariu innumerabilis). It 

 is somewhat below normal size, and the egg sac is narrower than usual. It spreads 

 slowly, but is often extremely abundant and injurious. The remedies in use in East- 

 ern cities consist of heading in the tree; i. e., cutting off the branches, and in 

 spraying by means of a double-acting force pump, mounted upon a tank cart, with 

 the ordinary kerosene soap emulsion. — [July 2?, 1890. J 



The Wheat Straw Isosoma in the State of Washington. 



We have discovered a worm in the stalkof our present crop of wheat which is un- 

 known to us as farmers. The insect is found sometimes in the space between the 

 joints, but oftener in the first joint from the ground. Our wheat fields have shown 

 spots of poor grain in unaccountable areas to such an extent that we have sought for 

 the cause. We have discovered this small worm to be very numerous, but it does 

 not seem to be of any especial damage to the plants, as it is found in the healthy stalks 

 equally with those of poorer growth. Would you kindly refer the specimens which 

 I inclose to the Entomologist, and send report to Walla Walla Farmers' Alliance? — 

 [Milton Evans, Secretary Northwestern Farmers' Alliance, No. 56, Walla Walla. 

 Wash.. July 17, 1890. 



Reply. — The insect which is damaging your wheat fields is a species very closely 

 related to the Joint-worm of the Eastern States. It is a species known as the Wheat- 

 straw Isosoma ( Isosoma tritici Riley). You will find this insect treated at some length 

 in the annual report of this Department for 1881-'82, pages 183-187. Unless present 

 in a wheat field in enormous numbers this insect damages the crop but little; but in 

 case a remedy is desired, it may be found in burning the stubble after harvest, as the 

 majority of the worms occur in the straw below the point of cutting. As most of the 

 fields are allowed to grow up with the weeds after harvest, it will be an easy matter 

 a little later to run a mower through the fields, and after the weeds are dried the 

 whole surface of the field can be burned over — [July 24, 1890.] 



Suppposed Enemy under Pear Bark. 



Inclosed please find two bits of bark from a pear tree. The tree is at least twenty- 

 five years or more old; it is an old-fashioued, mealy summer pear. There have been 

 for years places where the bark has been off, and under it there looked to be a white 

 stringy saw-dust. This morning I applied .some of it to the examination of a 16-power 

 pocket glass and found it to be worms, the longest being one-eighth of an inch long. 



