Mycorrhizae and fertiziler nursery treatments impact yellow-poplar seedlings outplanted at three locations in East Tennessee

Yellow-poplar (Liriodendron tulipifera L.) seedlings were grown in mycorrhizal inoculated nursery beds with four levels of fertilization for one growing season.

Seedlings were outplanted in April 1979 at three locations in East Tennessee, representing different site qualities. Measurements of seedling height, root collar diameter and survival were made for each of the first two growing seasons. Foliage samples were collected in September 1980 and analyzed for foliar nitrogen and phosphorus concentration.

Nursery fertilizer treatments significantly affected the height and root collar diameter of the seedlings. However, the fertilizer treatments did not affect seedling growth after outplanting, consequently the differences brought about by nursery fertilizer treatments were smaller after two years.

Mycorrhizal inoculation did not greatly affect seedling size in the nursery; however, postplanting growth was affected by the mycorrhizal treatment in the nursery. As a result of the mycorrhizal effects on the outplanted seedlings, differences in seedling height have become larger after two seasons of growth. The seedlings from the Glomus spp. treat ment grew the most, followed by seedlings from the natural inoculum, Glomus mosseae and no inoculum treatments.

Seedling survival and foliar concentration of nitrogen and phosphorus were not significantly impacted by treatments in the nursery.

The outplanted seedlings exhibited highly variable growth rates at one location, apparently independent of preplanting treatments. A separate study was initiated to determine if the growth differences were attributable to site variability. Five distinct soils were found on that site. These soils varied significantly and affected the growth and survival of the outplanted seedlings. Differences in seedling survival among the soils may have been aggravated by competition for soil moisture between the seedlings and a well-established grass cover.