DISEASES OF PLAMS. 57 



SEEDS— WEEDS. 



A machine for preparing seeds that germirate with diulculty ( nrairisclnr. 

 Iiuidw. Zl;/., 6? {1S94), i\>*. ID, p. SO).— A. l)rit'l' dcsciiptioii, with ilhistiatiun. 



German vs. American red clover seed — a rep y to Prof. Nobbe, J. L. .Texskx 

 ( I'licshr. LdinlmiuHl, 30 {1S04), pp. 214, 215, 224-220). 



Nevada weeds, F. H. Hillman (Xtvada Sta. Btil. 22, pp. 11, ph. .3).— iJcscription.s 

 and specimens are given of squirrel-tail grass (Hui-denin jiihainm), Fraiiseria liooker- 

 iana, poverty weed (Ira a.rillaris), shepherd's pnr.se {('apsvUa hiirsa-paatoriif), and 

 pepper grass {Lepidium iiilermedium^). The first three arc illustrated by photo- 

 engravings. 



DISEASES OF PLAKT3. 



Potato diseases and their treatment, S, B. Gt^een {Minncmid Sfa. 

 Bui. 32, pp. 2ir>-22:^, fi(/s. .3). 



Synopsis. — Popular reports on treatment for tiie prevention of potato rot and ])otato 

 scab. 



Potato rot (pp. 215-221).— The hitc blight, or rot {Phijioplithora 

 mfestans), of potato is described and illustrated. References are made 

 to experiments couditcted at various stations for the prevention of this 

 disease. At this station 2 experiments were conducted, and they 

 showed a considerable increase in the crop as the result of the applica- 

 tion of Bordeaux mixture. In the first experiment there was an 

 increase of about 30 per cent, due to the appli(;ation of the fun.nicide. 

 The tops of the treated rows were more vigorous in every Avay, and 

 remained fresh and green for more than 2 weeks after the tops of the 

 untreated varieties were dead. In the second experiment there was 

 little or no blight present in any i^art of the field, yet the difference in 

 the appearance of the treated tops was quite marked. When harvested 

 the yield from the treated j^lat showed an increase of 50 bus. per acre 

 over the check. This increase seemed to be due to the larger size of 

 the treated tubers. In the treated rows all the potatoes were merchant- 

 able, while in the others about 10 bus. per acre of tubers were too small 

 lor market. The cost of material and application need not exceed $4 

 per acre, and as the increase due to the treatment is often as large as 

 50 bus. per acre it will considerably more than pay for the a])plication. 

 Paris green and London purple as insecticides are recommended to be 

 used in connection with Bordeaux mixture. 



Potato seal) (j^p. 222-228). — Illustrated descriptive notes on the cause 

 of potato scab (Oo,s;2^ora sea ?>iev). As showing the importance of pre- 

 venting drainage water from fiowing from infected to noninfected 

 ground, the author cites a case in which water from an infected fiehl 

 flowed over a field never ]»reviously used for j)otatoes. The results 

 clearly showed that the scab fungus was carried from one field to the 

 other. 



