180 SEEDING AND PLANTING 



A quart of poisoned grain is sufficient for about sixty baits, 

 which are most effective when scattered near logs or stumps, along 

 trails, and near burrows. If not exposed to rain, the bait retains 

 its effectiveness for a long time. 



Pocket gophers are not only injurious to young trees but also 

 to the seed during germination. A poisoned bait of various vege- 

 tables, particularly sweet potatoes, is reported by Piper as most 

 effective in killing these animals. The bait is prepared as 

 follows: 



c. Baits of vegetables should be cut about 1 inch long and 

 J inch square, and should be washed and drained. Slowly . sift 

 | ounce of powdered strychnine (alkaloid) and T V of this quantity 

 of saccharin (ground together in a mortar) over about 4 quarts 

 of the dampened bait, stirring to distribute the poison evenly. 



The bait is placed in the animals' runways. An iron rod is 

 forced through the soil into the underground runway, which 

 usually is found a few inches below the surface and parallel with 

 it. One or two pieces of bait are dropped therein and the opening 

 is closed. 



The cost of poisoning rodents varies between wide limits, de- 

 pending upon the method of distribution of the bait, the closeness 

 of spacing in its distribution, the number of times the bait is 

 distributed, and the relative size of the strip surrounding the 

 seeded area necessary to poison. When it is distributed at the 

 rate of 1 bushel of poisoned bait to 40 acres, at intervals of 15 

 feet in rows 40 feet apart, the cost of a single distribution varies 

 from 10 to 20 cents per acre, depending upon the locality and the 

 cost of labor. 



Seed-eating birds are usually not harmful to direct seeding ex- 

 cept during a short period immediately after germination when 

 the seed coats are raised above the ground with the cotyledons 

 still enclosed within them. When they are bitten off at this time, 

 the young plant is destroyed. 



When there is danger that the poisoned grain will be taken 

 by birds, it should be placed in the burrows of animals, under 

 projecting stones and logs, and in other places out of their 

 reach. 



The difficult problem of effectively eliminating seed-eating 

 rodents, particularly white-footed mice, from badly infested sites 

 has not been solved. Poisoning is by no means uniformly sue- 



