Had a Word For It! 



"The noisome lueeds that ivithout profit suck 

 The soiT s fertility from icholesome Jlouers." 



Many of us have seen a field de- 

 pleted in fertility and displaying an 

 abundant weedy growth — evidence to 

 the ability of weeds to grow and re- 

 produce under conditions intolerable 

 to domesticated cultural crops. 



Weeds Underestimated? 



It has been said that the weed is a 

 plant whose virtues have not yet 

 been discovered. There is already 

 some indication that weeds may im- 

 prove soil fertility. When weeds 

 die and subsequently decompose, the 

 soil phosphorus and other nutrient 

 elements originally taken up by them 

 are released during the decomposi- 

 tion process. Many organic decom- 

 position products also act chemically 

 to increase the availability of soil 

 phosphorus. Thus, weeds may play 

 a leading role in releasing fixed phos- 

 phorus and other soil elements. 



Potassium is an essential plant 

 nutrient, particularly important in 



grass-legume mixtures. Grasses and 

 weeds are so efficient in their uptake 

 of soil potassium that they can grow 

 normally when the level of soil potas- 

 sium is too low to support legume 

 growth. Weeds, then, place the pot- 

 ash supply for the legume in double 

 jeopardy. 



Under fertile soil conditions, com- 

 mon cultivated-land weeds, such as 

 pigweed, chickweed, and purslane, 

 may accumulate large amounts of 

 potassium. For example, purslane 

 was found to contain 8.43 percent 

 potassium, whereas near-by onion 

 plants had only 2.23 percent. 



Weed Control Only Solution 



The weed problem is as great as 

 the number of weeds allowed to grow 

 unhindered. The only way to stop 

 weeds from impeding plant growth 

 is, obviously, to keep them under 

 control. 



In the bargraph below, weeds are represented as having a greater mineral content than their 

 associated cultural plants, except in potatoes where nitrogen, potassium, and calcium were found in 

 lesser quantities. The cultural plants have been given the value 100. 



Relative 



Content 



Weeds 



Cultural Plants 



1. Graiiland (Timothy) 



2. Onion Plonti 



3. Potofo Topi 



4. Corn Planti 



1 2 3 



Phoiphoru! 



1 2 3 

 Potassium 



2 3 



Calcium 



12 3 4 

 Magnesium 



