270 PASTORAL AND AGRICULTURAL BOTANY 



LABORATORY WORK 



Suggestions to Teachers. It is desirable, although probably not feasible on account 

 of lack of time, for the students to make a collection of weed seeds. These can be 

 kept in vials in the manner indicated in the laboratory work at the end of Chapter 12. 

 A collection of forty-eight weed seeds, or twice that number, if two boxes of vials are 

 used instead of one, will be very helpful in the identification of doubtful weed seeds. 



The botanical laboratory, where agricultural botany is taught, might form an 

 agricultural collection, such as is outlined in a bulletin issued by the College of Agri- 

 culture, Agricultural Extension Service, University of Missouri, Columbia, Missouri, 

 November, 1915. An outline of the suggestions in Project Announcement No. 2 is 

 given herewith. 



AGRICULTURAL COLLECTIONS FOR LABORATORIES 



Farm Crops Laboratory Material 



Mounted Laboratory Material 

 Sets 



I. Types of wheat. Spikes and threshed grain. 

 II. Varietal types of common wheat. 



III. Types of oats. Panicles and threshed grain. 



IV. Types of barley. Spikes and threshed grain. 

 V. Types of clovers. Head and threshed grains. 



VI. Sorghum types. 



VII. Economic grasses. Spikes and panicles with threshed seeds. 

 VIII. Botanical types of corn. 

 IX. Varieties and types of millets. 

 X. Miscellaneous cereals. 



XI. Seeds of miscellaneous forage, root, fiber and other plants. 

 XII. Pathological specimens of loose smut of wheat, covered smut of wheat, loose 



smut of barley, smuts of corn and oats, etc. 



In addition to the above, there should be accumulated book illustrations, photo- 

 graphs, score cards and maps showing distribution and economic importance of the 

 various crop plants. 



The teacher should have on hand several pounds of commercial seeds purchased 

 in the open market, such as alfalfa, red clover, wheat, rye and oats. These are accumu- 

 lated for use in the following exercises. 



LABORATORY EXERCISES 



i. Small measured quantities, either by volume, or by weight, of some seed sample 

 (as above) should be distributed to every student in the class, who should make an 

 analysis of the samples distributed. The good seeds should be placed in one pile, 

 the weed seeds in another, and the impurities in a third. An estimate should then be 

 made of the percentages of purity of each of the samples. 



