These nematodes, sold under the names of Scanmask and Nemasys, are microscopic, wormlike creatures that will destroy the fungus gnats but are not harmful to people, pets, plants, or earthworms. These products can be used whenever the soil is not frozen and will keep working for many months.
Vegetative structures. There are three levels of integrated organization in the vegetative plant body: organ, tissue system, and tissue. The organs of the plantâthe roots, stems, and leavesâare composed of tissue systems (dermal tissue, ground tissue, and vascular tissue; see below Tissue systems).
The plant body consists of two basic parts--- the shoot system and the root system. Shoot system is above ground and includes organs such as leaves, buds, stems, flowers, and fruits. The functions of the shoot system include photosynthesis, reproduction, storage, transport, and hormone production.