Weed control and light and water competition in the establishment of a natural stand of Pinus patula in Mexico

Abstract

This study was conducted in a natural regeneration area of Pinus patula to evaluate the effect of weed competition on photosynthetically active radiation, soil water content, and plant water potential in a two year-old Pinus patula seedlings. Using a complete randomized experimental design trhee treatments of weed control, consisting in manual weed control every two, four and six months, were tested against no weed control. Results indicated that a high weed density in the stand decreased the soil water moisture, the low levels of water negatively affecting the water potential in Pinus patula seedlings, particularly during the dry season. A high weed density caused a dramatic reduction of the photosynthetically active radiation reaching the soil, thus increasing the light competition between pine seedlings and weeds.