1 3 o WEEDS OF FARM LAND 



investigation has shown that it is really far more cosmopolitan. 

 It is as common on medium loams as on light loams and 

 sand, and it is also seen quite often on the heavy loams and 

 clays. In fact the proportion of the number of occurrences 

 in these situations reaches 50 per cent, of those on all the 

 other soils. Poppies are frequently dominant in 367 occur- 

 rences they took first place 93 times but they are never domin- 

 ant on clay, and but rarely on heavy loam. Here again the 

 popular mind is astray, as the records of dominance are nearly 

 as frequent in proportion from medium loam as they are from 

 sand and sandy soils, though light loams have a lead in this 

 respect. Equally striking is the frequency with which the 

 weed is scarce 69 times in the 367 observations. Naturally 

 enough, this scarcity is more marked on the clays and heavy 

 loam, but it is also very noticeable on all the lighter types of 

 soil. 



Sand wort (Arenaria serpyllifolid] is apparently localised in 

 its distribution. It was seen 103 times in Norfolk, but only 

 seven times altogether in the other districts visited. It is 

 quite possible that it may occasionally have been overlooked, 

 as sometimes it closely resembles small forms of Stellaria 

 media, but it is improbable that it would have escaped detec- 

 tion to any serious extent. It has a much stronger dislike of 

 heavy soils than has Papaver rhceas, and also it shows a cer- 

 tain preference for chalk. Sandwort is rarely dominant and 

 rarely scarce ; it avoids extremes and simply takes its place 

 as an inconspicuous member of the weed flora, seldom playing 

 any striking part. 



Soft crane's-bill (Geranium molle] and sun spurge (Euphorbia 

 helioscopid] resemble one another in that in addition to being 

 scarce on heavy land they are also less prevalent on the lighter 

 soils, including sandy and light loams and sand. Soft crane's- 

 bill was once seen dominant on sand, and is rather often scarce 

 in quantity, but the sun spurge never dominates and is more 

 usually scarce on any kind of soil. The latter plant is a most 

 insignificant member of the weed community, and were it not 

 that it thrusts itself upon one's notice by its peculiar colour 

 and conformation, would often run great risk of being over- 

 looked. 



Corn chamomile (Anthemis arvensis} is less common than 

 some of the other mayweeds, and is hardly found at all in 

 some districts. It very occasionally dominates on light or 

 chalky soils and is often scarce on any soil. 



