388 WEEDS 



Of course this does not apply to those weeds having a very per- 

 sistent underground rootstalk. 



(5) Crops of weeds bearing mature seed should be mowed, 

 raked and piled into compost heaps to rot instead of plowing them 

 under directly. The rotting process will destroy many of the weed 

 seeds. 



(6) This composting process should be used with manures 

 which are known to be badly infested with weed seeds. 



(7) Beparticularly diligent in fighting weeds new to your region. 



(8) Make the best use possible of sheep, hogs and other animals 

 for the control of weeds in pastures and elsewhere. 



(9) Use rotation of crops for the control of weeds, if for no 

 other reason. 



(10) Use chemical sprays in all cases where they can control 

 the weeds in a wholesale manner and with economy. 



(11) Do everything possible to aid in the enforcement of weed 

 laws of your state ; both the laws relating to clean seed and those 

 relating to the growth of noxious weeds. 



FIELD AND LABORATORY EXERCISES 



1. Study Growing Weeds. Many field trips should be taken to study 

 weeds as they grow in the fields. Make lists and indicate the kind of place in 

 which each is found. In the laboratory or study room, these should be grouped 

 according to their length of life as annuals, biennials, and perennials. The 

 perennials may again be sub-divided into those which have runners and running 

 rootstalks. 



2. Freshly collected specimens should be brought to the laboratory and 

 classified the same as the lists have been classified before. This will aid in be- 

 coming familiar with the name as well as with the length of life of each weed. 



3. Press and dry good specimens of weeds showing all the characteristic 

 parts as well as possible, such as the underground rootstalks, runners, bulbs, 

 flowers and stalks. Mount these on sheets as botany specimens. The label 

 for each should give the name, family, group name indicating length of life, 

 kind of place where found, and date of collection. 



4. Spraying to Kill Weeds. Try different spray materials in combating 

 such weeds as mustard, wild aster and others. 



5. Salt and Chemicals on Weeds. Where weeds or grass come through 

 cracks in walks, or in other similar places where they are not wanted, try kill- 

 ing them with salt. Use copper sulfate solution on some of them. Which do 

 you consider better? 



6. Sheep May Kill Weeds. In a pasture where sheep are grazing, put their 

 salt on some of the bad weeds and note the results later. 



7. Weeds Shipped in Hay. Examine packing materials where goods have 

 been shipped in hay, straw and similar litter. Put some of this material in a 

 sieve, and try to shake put weed seeds on a smooth floor. Sprout some of 

 these seeds hi a box of soil. Determine the kinds of weeds, either by the seeds 

 or from the sprouts. 



8. Weed Seeds in Feeds. Obtain samples of feeds at feed stores. Try 

 sprouting a number of these by planting them in boxes of soil. Samples of 

 molasses feed are specially apt to be laden with weed seeds. 



