Similar to the case of the neighbourhood density described above, environmental heterogeneity may cause repeller or accumulator effects in the absence of species interactions if the focal species is predominantly located in areas of low or high sapling diversity.
He started planting seeds at his five-acre nursery in Jacksonville, and now offers foot-high saplings for $35, complete with a tree-planting kit that includes a growing tube to protect them from deer and harsh weather.
Hundreds of metre-high saplings are being deliberately infected with the disease so scientists can watch how it develops, and establish which of the clones are genetically immune.
(The knee-high sapling is surrounded by a ten-foot chain-link fence topped with barbed wire).
And overhanging the teahouse is a five-needle Himalayan pine, a knee-high sapling when planted in the late 1960's.
Mortality was higher during the 1983 drought than over the next 10 years, but the 1995 2000 census had the highest sapling mortality in the entire period (Table 1).
During a visit to the Indian lightbulb plant back in 2001, the year he took the helm at Philips, Kleisterlee donned a Philips blue turban and planted a knee-high sapling.
The drought impacts on mortality rate in two size classes were positively correlated across species, that is, species suffering higher sapling mortality during the drought also suffered higher tree mortality during the drought.
However, species with higher minimum mortality consistently showed both higher sapling mortality and higher mortality at larger stem sizes (Spearman's Rank Correlation p<0.05 for both trends).
Nine infected and marked L. dispar larvae at 10 dpi and 21 uninfected newly-moulted third instars (= test larvae) were placed onto potted 2-year-old and 1-m high oak saplings (Q. petraea).
Farther up, a tangled spray of waist-high maple saplings bowed and nodded, burnished wine-red.
