Origin of pyrethrum
Examples from the Web for pyrethrum
The pyrethrum may be used dry or in water, at the rate of a tablespoonful to two gallons.
The remedy prescribed is a powder in which pyrethrum is the chief ingredient, sprinkled about the shelves.A Book for All Readers|Ainsworth Rand Spofford
Howard recommends thoroughly rubbing into the fur a quantity of pyrethrum powder.Handbook of Medical Entomology|William Albert Riley
Pyrethrum is also used largely, but it only stupefies the mosquitoes temporarily instead of killing them.Insects and Diseases|Rennie W. Doane
The pyrethrum powder is considered the best for this purpose, but is expensive and difficult to procure in the pure state.The Dollar Hen|Milo M. Hastings