CIRCULARS OF THE BUREAU OF PLANT INDUSTRY. 
Page. 
Circular No. 28. — Clover-Seed Production in the Willamette Valley, 
• Ikegon— Continued. 
Means of securing a stand of red clover 5 
Crop rotations practiced by growers of clover . 7 
Pasturing and clipping clover 8 
The use of land plaster in growing clover 9 
Harvesting clover for seed 10 
Treating clover seed affected with honey dew 12 
Insect pests of red clover 12 
How clover-seed production and live stock improve the soil 12 
Summary 14 
Circular No. 29. — Experiments with Egyptian Cotton in 1908. 
Introduction ."> 
Imports and prices of Egyptian cotton in 1908 5 
Spinning tests of 1907 fiber 6 
Results of exp' riments in 1908 7 
Experimental fields at Yuma and Sacaton, Ariz 7 
Comparison of imported and acclimatized seed 8 
Different behavior of the different plantings 9 
Yields 9 
Quality of the fiber 11 
I 'hint- breeding work 12 
Planting distance 14 
Irrigation methods 14 
Productiveness in relation to time of planting and rate of irrigation.. 14 
Crossing with other varieties 15 
Diseases and insect enemies 16 
Alkali resistance 18 
Present outlook for Egyptian cotton in the Southwestern States 18 
Summary 20 
Circular No. 30. — Improvement of the Oat Crop. 
Need for improvement 3 
Lines along which improvement can be effected 4 
Methods of improvement 4 
Mechanical selection 4 
Introduction of new seed 4 
Use of the seed plat 5 
Individual plant selection (i 
Hybridization 10 
Varieties 10 
Conclusions 10 
Circular No. 31. — Notes on the Number \m> Distribi tionof Native Legi mes 
in Nebraska and Kansas. 
Introduction ■"> 
Nitrogen fixation in soil by wild legumes 3 
Difficulty of making investigation '■'> 
Legumes form a huge part of our native Horn t> 
Nodules abundant in wild legumes (> 
Factors influencing the distribution of wild legumes 7 
Legumes are crowded out on the richest soils 7 
Number of genera ami species in different localities 7 
Value of legumes in pastures 8 
Lesson of the prairie legume for the farmer 8 
