SEEDS WEEDS. 959 



SEEDS WEEDS. 



Clover seeds and their impurities, F. II. Hili^man {A\'vada Sta. 

 Bid. .'(7. j>i>. OL\ji<ix. ,9J). — P^xtended .series of studies on clover seeds 

 and their impurities arc reported. The author has investig-ated a 

 number of kinds of clover seed and separated from them the different 

 kinds of weed seeds occurring in them. The characteristics of the 

 different clover seeds are tigured and described and lists given of the 

 kinds of weed seeds and percentages found in the different samples 

 containing them. Studies are given of alfalfa seed, red clover, white 

 clover, alsike clover, crimson clover, Japan clover, Bokhara clover, 

 yellow sweet clover, yellow trefoil, esparcet, and serradella. From 4 

 to 00 samples of each of these seeds were examined. The most com- 

 mon Aveed seeds were Plaidago ragelil^ P. lanceolata., P. aristafa., 

 C^MnicBraphis viridis., C. glauca., Poly gomm% per sicaria^ Clienojxjdlwn 

 alhirm^ Pvmex crhpnx^ R. acetoi<elJa, and EHphoi'hia iivtans. The dif- 

 ferent weed seeds are ffgured and described in considerable detail. 



Experiments in preserving forest- tree seeds {Bid. Soc. Cent. 

 Ford. Btlg., 7 {JOOO), ^^o. 7, pp. olJ^-olO). — Experiments are reported 

 with acorns and chestnuts, in which the relative efficiency of autumn 

 and spring planting is compared. The autumn plantings were made 

 in two lots, in one of which the acorns were covered with leaves to a 

 depth of from 5 to 6 cm., while in the other they Avere planted in 

 trenches to a depth of 0.1 meter or a little less. The seeds for spring 

 plantings were preserved as follows: In trenches, in piles covered with 

 soil and others covered with leaves, in baskets submerged in water, and 

 stratified in sand in a dry cave. The results, as shown by the germi- 

 nation and growth of the different lots, are tabulated, from which it 

 appears that in a sandy loam during an ordinary winter autumn seed- 

 ing is preferred to an}- of the methods of preserving the seed and 

 planting in the spring. This is shown not only by the fact that more 

 germinations were obtained, but that the work could be done at a sea- 

 son of the 3'car when there was less demand for attention to the nurs- 

 eries, as is the case in the spring of the year. 



The effect of hydrocyanic-acid gas upon the germination of 

 seeds, C. O. Townsp:xd {Proc. A//ie/: .i.s-.s-w. Adv. -Vt-/., 4'"'' {ISOO), p. 

 297). — Seeds in both a dry and damp state were tested with different 

 strengths of gas and for different periods of time. In the case of dry 

 grains and seeds it was found that they were able to withstand for 

 several weeks an atmosphere of hydrocyanic-acid gas man}^ times 

 stronger than that required for the destruction of insect life. Under 

 these conditions a slightly accelerated germination was observed, and 

 the suT)sequent growth of the seedlings was slightly above normal. 

 Seeds that had })eeji soaked in water were very sensitive to the presence 

 of the gas. Three oue-hundredths of a gram of potassium cyanid per 



