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The sycamore (Acer pseudoplatanus L.) shows good adaptability to climate change and it could be used more widely in plantations in Europe and Bulgaria. The purpose of this study is to analyse and establish the condition, growth and productivity of plantations and natural stands under different habitat conditions in Bulgaria. All plantations and natural stands over 30 years of age, pure or dominated by sycamore, were evaluated on site. The volume of natural stands varies from 216 m3 ∙ha-1 to 944 m3 ∙ha-1. The plantations’ growing stock at the age of 40 is 399 m3 ∙ha-1, 70-year-old plantation has a stock of 810 m3 ∙ha-1. At the age of 50–55, the Norway maple (Acer platanoides L.), the silver linden (Tilia tomentosa Moench.), the hornbeam (Carpinus betulus L.) and the European beech (Fagus sylvatica L.) reach and exceed the growth in height of sycamore, but not in diameter. Under optimal conditions, sycamore can produce amount of volume that meets the requirements for intensive crops.

The purpose of this study is to analyze existing silvicultural experience related to the sycamore using literary data in order to optimize future work with the species. The discussion looks into matters related to: ecological requirements, seed propagation, vegetative propagation via rooting of stem cuttings and grafting, natural regeneration specifications, creating and cultivation of forest plantations, growth and productivity of the stands, and silviculture activities dedicated to the production of high-quality timber.

The reaction after treatment with selective herbicides was carried out in a nursery plot for production of one-year-old poplar saplings from the type 0/1 from the cultivars ′I-214′ and ′Vernirubens′. Water solutions of the 4 herbicides (H1–H4) with a concentration 5 ml.l-1 and a control variant were tested. Treatments were carried out in five terms: May, June, July, August and September. Final measurements were carried out after the growing season. The estimation of the influence of each herbicide was done after the following indices: survival, height and diameter of the stem; thickness and number of roots of first grade; relative moisture of wood of poplar saplings. The results showed that tested herbicides do not influence on the survival of saplings with the exception of a negative influence on cultivar ′Vernirubens′, caused by the herbicide Select. Saplings of cultivar ′I-214′ have faster growth in height than cultivar ′Vernirubens′. Tested cultivars show specific reaction to applied herbicides and best tolerance to H3 (350 g.l-1 Butachlor + 350 g.l-1 Propanil). Herbicides H1 (150 g.l-1 Fluazifop-P-butyl) and H4 (240 g.l-1 Oxyfluorfen) oppress less the growth of saplings at both cultivars, compared to the outlined depressive effect of the herbicide H2 (240 g.l-1 Clethodim). As most suitable was determined the herbicide H3. In the course of production, weed control could be carried out with the help of this herbicide during all phoenophases of the development of saplings.