Study on the thinning experiments of Pinus elliottii seed gardens

The thinning of P.elliottii based on the determination results of the filial generation and the action of present generation,can increase the production of seeds.Seed rates by thinning at the following levels:thinning in high level was 62%,thinning in middle level was 39%,thinning in low level was 28% and no thinning was 22%.The single tree seed rate by thinning at different levels as above was 400∶200∶120∶100,and rate production in mu was 411∶208∶119∶110.In the high-yield seed period the best way was to keep 8 to 10 per mu,and with a strong clone,only keep 6 to 8 per mu.