Extracts of pyrethrum flowers are now generally available commercially, and these give fairly good results in the destruction of house flies in buildings.
Most of the sprays of pyrethrum extract contain kerosene oil as a carrier, and undoubtedly the kerosene has much to do with the toxicity of the spray.
Calceolarias, Verbenas, and Zonal Pelargoniums, with a border of Pyrethrum or Cerastium--and that is about all.
Thus mercury internally promotes an increased salivation, and pyrethrum externally applied to the excretory ducts of the salival glands.
After the plants begin to head, pyrethrum or salt water may be used.
Hellebore and pyrethrum are useful when it is not advisable to use arsenical poisons.
The Feverfew is one of the wild Chamomiles (Pyrethrum Parthenium), or Matricaria, so called because especially useful for motherhood.
Good-sized groups of Pyrethrum uliginosum are given a place among the Asters, for though of quite another family, they are Daisies, and bloom at Michaelmas, and are admirable companions to the main occupants of the borders.
Should worms cause trouble, dust the plants with a mixture of one part of pyrethrum powder to six of fine dust.
Previous experience with pyrethrum was not very satisfactory.
Such rooms of course require a thorough cleaning or it is sometimes possible to kill the fleas by a liberal use of pyrethrum powder or benzine or to fumigate.
Pyrethrum is also used largely, but it only stupefies the mosquitoes temporarily instead of killing them.
These yield the pyrethrum of commerce so largely used as an insecticide, and which is said to form the chief ingredients in various flea powders.
Pyrethrum Pyrethrum (Chrysanthemum) cinerariaefolium grows well from seed and is an attractive garden plant with pretty, marguerite-like flowers.
When flies are very abundant in a room they can be most readily gotten rid of by fumigation with sulphur, or by the use of pure pyrethrum powder either burned or puffed into the air.
Howard recommends thoroughly rubbing into the fur a quantity of pyrethrum powder.
All cracks and openings should be closed with strips of paper and fumigation with burning sulphur or pyrethrum carefully carried out.
It is easy to drive the flies from houses or tents by burning pyrethrum powder inside; this either kills the flies or stupifies them so that they do not bite for some time thereafter.
Make it a point to keep the larger-growing kinds, such as Coleus, Pyrethrum and Centaurea, under six inches in height rather than over it.
Pyrethrum uliginosum is a wonderfully free bloomer, growing to a height of three or four feet, therefore well adapted to the middle rows of the border.
One of the dark copper-colored varieties would show to fine effect if surrounded with either yellow Pyrethrum or gray Centaurea.
The whites are Dahlias Constance and Henry Patrick, Pyrethrum uliginosum, the charming perennial Aster Colerette Blanche, a taller white or yellowish white Aster with rough stems and harsh-feeling foliage that I know as A.
Just put a layer of pyrethrum in the bottom of your bottle," answered the druggist, "keep it corked tight, and you can make every bug in your yard die happy.
Pyrethrum is a powder that is harmless to people (though of course you must not eat it), but the least smell of it kills insects.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "pyrethrum" in a variety of sentences. We hope that you will now be able to make sentences using this word.
