HORTICULTURE. 841 



in rye. The seeds of lamb's quarters and pepper grass appeared in 14 of the 

 16 crop seeds examined, while dodder seed appeared only in alfalfa and red 

 clover. Green foxtail and lamb's quarters were the most common weed seeds 

 found. Of the millet samples examined, 96.2 per cent contained green foxtail 

 seed. A iax'ge number of all samples tested were below the standard of purity. 



On the average, all germination tests gave a higher average in 1911 than 

 in 1910. Brome grass had a very low percentage of germination. The average 

 germination of hard seeds in alfalfa was 16.125 per cent, in medium red clover 

 10.45 per cent, in mammoth clover 6.5 per cent, in white clover 19.41 per cent, 

 and in alsike clover 12.55 per cent. Some tests of alfalfa at the laboratory 

 showed from 50 to 75 per cent of hard seeds. 



The approximate number of various crop and weed seeds per pound was 

 determined and is reiwrted in tables. 



[Seed analyses and experiment station results], F. G. Stebler (Landw. 

 Jahrb. Bchwciz, 25 {1911), No. 5, pp. 1/(9-170). — These pages report the results 

 of purity and germination tests of the seeds of legumes, grasses, grains, fiber 

 crops, root crops, and forest trees at the Zurich Seed Control Station. They 

 also give a brief reiwrt of other work under way (E. S. R., p. 239). 



Period of germinability of the seed of Cuscuta epilinum, A. Herzog (Deut. 

 Landw. Presse, 89 {1912), No. 21, p. 321, figs. 3). — A table containing the re- 

 sults of annual germination tests of the seed of C. epilinum, conducted during 

 the period 1897-1911, indicates that the percentage of the seed which germi- 

 nated in the first 5 days of the test gradually decreased from 90 in 1897 to 

 4 in 1906, and that the seed appeared to be entirely dead during 1910-11. 



HOETICULTURE. 



Report of the horticulturist, C. F. Kinman {Porto Rico 8ta. Rpt. 1911, pp. 

 24-27, pis. 3). — A progress report of the year's work with fruits, vegetables, 

 and miscellaneous plants (E. S. R., 25, p. 740). 



In the cooperative fertilizer experiments with citrus fruits the complete 

 fertilizers continued to give the best results. A study of the navel oranges 

 growing in Porto Rico indicates that there is a great variation in regard to 

 the quality of the fruit. Material has been collected from difi'erent orchards 

 on the island and experiments to determine the cause of variation in quality 

 are under way. The evidence in some cases indicates that this difference is 

 due to bud variation. 



Experiments in fumigating young pineapple plants taken from fields badly 

 infested with mealy bugs have shown that a fumigation strong enough to assure 

 clean plants at setting without injury to the plants can be made. The fumiga- 

 tion, however, has only a temporary effect and the customary practices must be 

 employed in keeping the plants free from insects after they have been set in 

 the field. 



The work with cover crops in citrus orchards was extended to pineapple and 

 coconut plantations. Cowpeas, velvet beans, sword beans, and pigeon peas have 

 given good results. Cowpeas were found to be inferior to the other crops for 

 summer planting on heavy soils as they mature early and often at a time when 

 the soil is too wet for replanting or caring for a new crop properly. The other 

 crops mentioned continue their growth throughout the season of heavy rains 

 and make a dense cover that keeps down all the grass and weeds and also 

 serves to prevent soil washing. Good crops of seed were secured from cowpeas 

 planted in the spring, although winter-grown crops of Canavalia and velvet 

 beans are more prolific. Canavalia and velvet beans planted on low, hea^'y 



