376 GLOSSARY 



Gypsum, land plaster consisting of calcium sulphate. 



Host, the plant on which a parasite lives. 



Humus, decayed animal or vegetable matter. 



Hybrid, the result of breeding two different species of animals or two differ- 

 ent species of plants together. 



Inoculate, to communicate bacteria germs by introducing matter contain- 

 ing a supply of them. 



Insecticide, a preparation for destroying insects. 



Irrigation, an artificial system of canals and ditches for supplying water to 

 cultivated lands. 



Kainit, a compound substance generally consisting of sulphate of potash, 

 sulphate of magnesia, and chloride of magnesia. Sometimes the analy- 

 sis shows sulphate of magnesia and chloride of potassium (Storer's Agri- 

 culture, Vol. II, p. 493). 



Kerosene Emulsion, a spray consisting of kerosene oil, water, and soap. 



Lactic Acid, acid derived from milk sugar. 



Larva, the immature form or grub of insects. 



Lichens, low mosslike and flowerless plants that grow on rocks and wood. 



Loam, a soil containing sand, clay, and vegetable matter. 



Marl, a mixture containing carbonate of lime, siliceous sand, and clay in vary- 

 ing proportions. 



Mildew, a cobweblike growth of fungi on decaying matter. 



Mold, a white furry growth found on damp bread, preserved fruits, manure 

 heaps, etc. 



Muck, decayed vegetable matter. 



Mulch, a light cover of leaves, straw, or some other substance spread on the 

 ground to preserve the moisture and to protect the roots of the plant. 



Nitrate, a soluble compound containing a readily usable form of nitrogen. 



Nodule, a little knot of rounded mass formed by certain bacteria on roots 

 of leguminous plants. 



Noxious, injurious or poisonous. 



Nutrient, any substance that promotes growth in plants and animals. 



Organic Matter, substances formed in the growth of plants and animals. 



Osmosis, the mixing of liquids of different densities through cell walls or 

 membranes. 



Ovary, the lower part of the pistil that bears the young seed. 



Oxidation, combining with oxygen to form an oxide. 



Parasite, any living form that derives its nourishment by preying upon some 

 living plant or animal: 



Perennial, living from year to year. 



Petal, a single leaf of the corolla or the inner colored envelope of the flower. 



Pistil, the seed-bearing organ of the flower. 



Pollen, the dustlike substance of the stamens which fertilizes the ovules or 

 seeds. 



Pollination, the transference of the pollen from the stamens to the pistils. 



Propagate, to cause plants or animals to increase their kind. 



