Resumen de Biomass production of loblolly pine seeded between rows of planted loblolly pine
A dual-cropping concept was tested by growing loblolly pine (Pinus taeda L.) for energy biomass in normally unused space between rows of a newly established pine plantation. Loblolly pine seeds were spot seeded in a 1.5 m wide swath between the planted rows of loblolly pine seedlings planted at 2 by 3 m spacing. At age 5 years, the direct-seeded trees from one of two seeded subplots of each plot were sampled for biomass and nutrient measurements. After subsampling, all of the direct-seeded material was removed from the subplot.
On plots without direct-seeded trees, phosphorus fertilization increased height of the planted trees from 5.8 to 6.4 m and the dbh from 8.3 to 9.2 cm at age 5 years. The presence of the direct seeded trees reduced height 0.2 m and the dbh 0.6 cm. The average dry weight of the direct seeded material was 10.2 Mg ha−1. Phosphorus fertilization had no effect on the growth of the direct-seeded trees after the first year. Water content (wet weight basis) of the direct seeded material was 62% in the needles, 52% in the branches and 56% in the main stems, which reduced potential fuel efficiency. Total energy produced over the 5 year period was 130,800 MJ ha−1.
