PROF. G. E. BLACKMAN, in a short paper on "Recent Developments in the Control of Weeds" (J. Roy. Hort. Soc., 73, 5 ; May, 1948), summarizes some useful results on the effectiveness of various selective weed-killers. Sulphuric acid gave the best control of goosegrass, Galium aparine ; methyl-chloro-phenoxy-acetic acid gave the best kill of shepherd‘s needle, Scandix pecten-veneris, and common red poppy, Papaver rhæas ; and dinitro-ortho-cresol was most toxic to scentless mayweed, Matricaria inodora, but also gave control equal to the acetic acid compound of P. rhœas. The use of sulphuric acid is still most effective, particularly against weeds of the onion crop. Spraying with this acid gives about 90 per cent of the yield obtained by hand weeding and hoeing, but at very much less expense in labour. Charlock is susceptible to control by growth-substance sprays at all stages from seedling to flowering, though poppies are susceptible only as seedlings.