Part 2

1. They rob cultivated plants of nutriment.

2. They injure crops by crowding and shading.

3. They retard the work of harvesting grain by increasing the draft and by extra wear of machinery. (Bindweed, thistles, red root.)

4. They retard the drying of grain and hay.

5. They increase the labor of threshing, and make cleaning of seed difficult.

6. They damage the quality of flour, sometimes making it nearly worthless. (Allium vineale L.)

7. Most of them are of little value as food for domestic animals.

8. Some weeds injure stock by means of barbed awns. (Squirrel tail grass, wild oats, porcupine grass.)

9. Some of them injure wool and disfigure the tails of cattle, the manes and tails of horses. (Burdock, cocklebur, houndstongue.)

10. A few make "Hair balls" in the stomachs of horses. (Rabbit-foot clover, crimson clover.)

11. Some injure the quality of dairy products. (Leeks, wild onions.)

12. Penny cress, and probably others, when eaten by animals, injure the taste of meat.

13. Poison hemlock, spotted cowbane and Jamestown weed are very poisonous.

14. Many weeds interfere with a rotation of crops.

15. All weeds damage the appearance of a farm and render it less valuable. (Quack-grass, Canada thistle, plantains.)

SOME SMALL BENEFITS.

1. They are of some use in the world to induce more frequent and more thorough cultivation, which benefits crops.

2. The new arrival of a weed of first rank stimulates watchfulness. (Russian thistle.)

3. In occupying the soil after a crop has been removed they prevent the loss of fertility by shading the ground.

4. Weeds plowed under add some humus and fertility to the soil, though in a very much less degree than clover or cow peas.

5. Some of them furnish food for birds in winter.

WHAT ENABLES A PLANT TO BECOME A WEED.

1. Sometimes by producing an enormous number of weeds. (A large plant of purslane, 1,250,000 seeds; a patch of daisy fleabane, 3,000 to a square inch.)

2. In other cases by the great vitality of their seeds. Shepherd's purse, mustard, purslane, pigeon-grass, pigweeds, pepper-grass, May weed, evening primrose, smart weed, narrow-leaved dock, two chick-weeds survive when buried in the soil thirty years at least, as I have found by actual test.

3. In each prickly fruit of a cocklebur there are two seeds, only one of which grows the first year, the other surviving to grow the second year.

4. Some are very succulent, and ripen seeds even when pulled. (Purslane.)

5. Often by ripening and scattering seeds before the cultivated crop is mature. (Red root, fleabane.)

6. Sometimes by ripening seeds at the time of harvesting a crop, when all are harvested together. (Chess, cockle.)