DepartmeiVtal Activities. IT 



DEPARTMENTAL ACTIVITIES. 



(Note. — The work of the several Divisions and Schools of Agriculture covers a wide 

 range of agricultural industry in the Union, and we give hereunder notes and observations 

 from certain of them treating with matters of special interest coming under their purview 

 month by month. The object of these notes, which are not concerned with general routine 

 work, is to inform the farmer of such matters as are calculated to be of interest and helpful to 

 him at the present time. — Editor.; 



THE DIVISIONS. 



ENTOMOLOGY. 



Call worms and Root-knot. — The warts on potato tubers and 

 the knots and galls upon tlie roots of many cultivated plants and 

 weeds are due, in most cases, to the invasion of such underg-round 

 parts by microscopic worms. These creatures are always so small 

 that with the naked eye they cannot be seen either in the soil or 

 when embedded in the tissues of the plants. Quite a powerful 

 microscope is needed to inspect them. At the time of writing- a 

 considerable interest has been awakened in potato diseases through- 

 out the Union, and quite a stream of warty potatoes flows to the 

 Division for examination. The trouble is known to be widespread, 

 and it is remarkable how little its true nature is recognized 

 by the majority of our correspondents. For this reason the follow-- 

 ing- brief summary of the nature and habits of the pest is submitted 

 for the readers of these notes. 



The worms in question, variously called eelworms, g-allworins, 

 and nematodes, are not insects, but belong' to the same brancli of 

 the animal kingdom as do the earthworms and those intestinal 

 parasites known as pinworms, threadworms, wireworms, and tape- 

 worms. They are in the soil, as a rule, when the crops are laid 

 down, and enter the surface layers of roots and tubers, and there 

 develop. The females become swollen with young' and have the 

 appearance of minute balloons. They can be discerned as small, 

 milk-like spots if the gall or wart is cut into particularly thin slices 

 with the help of a razor ; a penknife is seldom equal to the task of 

 cutting a thin enough slice. The presence of the worms in the plant 

 tissue sets up an irritation and the characteristic swellings follow. 

 Later on the swelling breaks down to decay, and an increased brood 

 of worms escapes into the soil. Many plants, especially tomato, 

 pumpkin, and melon vines may die outright as the result of gall- 

 worm attack. These worms do not live deep in the ground, and it is 

 for this reason that many trees thrive, although their surface roots 

 are full of gallworms. Peach trees, fig trees, and grape vines are 

 frequently infested, a fact which explains the numerous failures 

 where it is attempted to grow vegetables near by or among perma- 

 nent plants of this sort. Ordinarily, lands become infested either 



