Short leaf pine

This portion is called springwood (Sp) or eadywood. During the summer or later in the growing season, the cell wall thickness increases to 8—12 pm and the outside diameter decreases from 29—47 pm in short-leaf pine. These cells form summerwood (Sm) orlatewood. The sequential combination of seasonal cell types leads to the characteristic aimual ring (AR) of trees, which is more or less distinct in softwoods, depending on the species. 

Figure 3. Distribution of Thanasimus dubius pupae in loblolly and short leaf pine. (Reproduced with permission from Ref. 6. Copyright 1981, Entomological Society of Canada.)...

Bioassays of aqueous leaf extracts (1.25-5.0%) demonstrated dose-dependent inhibition of Scots pine (Pinus sylvestris L.) germination. Activated carbon removed the toxicity of the extracts. Aqueous extracts passed through E. hermaphroditum soil lost toxicity, while extracts passed through sterilized soil did not (Zackrisson Nilsson 1992). Other experiments showed that even a relatively short exposure (7 h) to aqueous leaf extracts had a persistent effect on subsequent growth of pine seeds (Nilsson Zackrisson 1992). 

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