Effects of different methods of site preparation on natural regeneration of Pinus sylvestris in Eastern Poland

Abstract

Mechanical site preparation (MSP) is commonly used to enable forest regeneration of clear-cuts. Less intense methods may be more suitable from an environmental point of view, but such a method can result in the lack of natural regeneration. We compare the influence of three MSP methods on natural regeneration of Scots pine. The methods differ in their degree of soil disturbance. The effects of MSP by forest plough (FP), active plough (AP), and forest cutter (FC) on density, quality, and biometric parameters of one-year old seedlings were determined. The highest density of seedlings was obtained in the FP treatment (188,000 seedlings ha ). The best quality seedlings were found in the FC variant, and the worst -in the FP treatment. Most biometric parameters of seedlings did not differ by MSP method, except for the root length and root:shoot ratio. By the end of growing season, in the FP treatment, 1-year old seedlings formed a top bud more than twice as often as the seedlings from the AP and FC treatments. The FP method led to the best Scots pine natural regeneration. The results obtained in the FC variant were not as good as in the FP method, though they were still acceptable from the silvicultural point of view. The FC method was the least intensive method of site preparation, yet it is considered the most appropriate from the environmental (soil protection) point of view.

Assemblages of carabid beetles (Col. Carabidae) and ground-dwelling spiders (Araneae) in natural and artificial regeneration of pine forests

“…Self-planting pine trees as an alternative forest cultivation method should be promoted by making conscious efforts to create suitable conditions, including appropriate soil preparation, for the development of such new tree stands (Pigan 2010). Studies on various technologies applied to soil preparation under artificial and natural pine stands focus mostly on agrotech-nical and economic issues (Szramka 2005, Hallikainen et al 2007, Aleksandrowicz-Trzcińska et al 2014) rather than ecological. Natural regeneration of forests is more difficult than artificial renewal and bears a higher risk of cultured failure.…”

Effects of Reforestation and Site Preparation Methods on Early Growth and Survival of Scots Pine (Pinus sylvestris L.) in South-Eastern Poland

“…Such densities seem satisfactory from the point of view of forest management [2], although they are lower than those reported in other Polish studies. In earlier research conducted by our team [38], seedling density reached 188,000 seedlings ha −1 in soil prepared by FP, 121,000 seedlings ha −1 in AP and 36,000 seedlings ha −1 in FM. In fact, the density can be even higher, up to 360,000 seedlings ha −1 [55].…”

“…Individual MSP methods more or less limit the growth of herbaceous vegetation in the clear-cut area [33,47]. In FM plots, vegetation left in undisturbed belts shades the seedlings and may compete with them for nutrients to some extent [36,38]. Regeneration of vegetation after site preparation with FP and AP should not occur before the end of second or even third growing season [33,48].…”

“…In such conditions, seeds have better contact with the soil surface and hence better moisture conditions (because of capillary water transport to the soil surface), compared to the humus or organic horizon [51,52]. As a result, seedling density in natural regeneration in a clear-cut area is highest after site preparation with FP, lower after the use of AP and lowest on the belts made by FM [38]. Our results confirmed this relationship only in the second year, in relation to seedlings self-sown in the second year in natural regeneration.…”

“…Their major advantage is that they affect the soil environment to a much smaller extent [30]. Plantations resulting from planting and self-sowing on soils prepared by FM are characterized by low density and survival rate but very good growth rate compared with other MSP methods [36][37][38].…”