With most perennials, the top growth dies down each winter and regrows the following spring. A pH of 7 indicates neutrality, less than 7 is acid, and greater than 7 is alkaline. R recharge - downward movement of water through soil to groundwater. Zones are identified by soil characteristics or plant communities and include the wet areas in and near streams, ponds, lakes, springs and other surface waters. S salinity - gardeners use this word when speaking of an excess of salts in the soil.
Salinity can harm many plants, causing leaves to scorch and turn yellow, and stunting plant growth.
Compared to clay soils, sandy soils contain much more soil and air, drain well, and warm quickly. They also dry out quickly, which necessitates frequent watering that washes out valuable nutrients. The stressful condition varies according to the particular plant and its needs. There are systemic insecticides, fungicides, and weed killers. T taproot - a main root that grows straight down.