284 ANNUAL, REPORTS OF DEPARTMENT OF AGRICULTURE. 



A test of this same extract made with hogs by the Bureau of Ani- 

 mal Industry at the experiment farm at Beltsville, Md., indicated a 

 much higher feeding value. 



The results of these two feeding tests appear so encouraging that 

 plans are being made to produce a larger quantity of extract this year 

 from material harvested at the time which appears to be most favor- 

 able for both extract and fiber production. 



As a result of the work on other materials conducted at Cumber- 

 land Mills, Me., it may be stated that broom-corn stalks have been 

 shown to be an immediately available material for paper making. 

 A large assortment of materials has been collected for experimental 

 work during the coming year and a quantity of finished paper has 

 been produced from several classes of crop waste handled both alone 

 and in combination with varying percentages of wood pulp. The 

 practical value of these papers for book purposes has been tested by 

 the use of five kinds in a circular of the bureau series. Considerable 

 additions have been made to the paper-making machinery in Wash- 

 ington. 



In connection with the paper project a large number of materials 

 are being examined by Dr. Albert Mann, who is making careful 

 measurements of the fibers of various wild plants and a study of 

 the relative proportions of various classes of tissue in the hope of 

 finding an exceedingly fine fiber which can be used for plating paper 

 made from coarser vegetable fiber, thus decreasing the amount of 

 foreign matter which is now used to give a smooth surface to book 

 papers. These studies have other important objects. 



Crop technology. — Owing to the very limited funds available, it 

 has been impossible to prosecute very actively the various projects 

 under the general head of crop technology, and attention has been 

 chiefly given to one of the miscellaneous projects, the study of plant- 

 attacking nematodes. A great variety of material has been sent to 

 this office within the past year for examination, and the investiga- 

 tions indicate that the injurious species of nematodes are very widely 

 distributed and highly injurious, especially in the Southern States. 



Studies have been undertaken to determine the normal nematode 

 population of certain classes of soils and of soils the crop history of 

 which is definitely known. By this means it is hoped to learn the 

 elfect of certain systems of cropping upon the most common and in- 

 jurious species. A large number of soil samples from the Arlington 

 Experimental Farm have been examined, and collections are being 

 secured from abroad for comparison with native species. 



The constantly increasing importance and widening scope of this 

 work demand a larger expenditure of time and energy each year. 



Illustration and projection. — Further improvements and adapta- 

 tion of projection methods in the measurement of cotton and paper 

 fibers have been worked out, and the value of the solar projector for 

 illustration has been further demonstrated. Improvements have 

 been made in the use of the camera lucida, and a study of screens 

 has resulted in the preparation of an aluminum-covered screen which 

 is considered an improvement for projection work. 



