Needles conifer

Ozone Flecking, stippling, bleached spotting, pigmentation conifer needle tips become brown and necrotic Oldest leaves most sensitive youngest least sensitive Palisade or spongy parenchyma in leaves with no palisade 0.03 59 4 hr... 

B. Schafer, P. Hennig, W. Engewald, Analysis of monoterpenes from conifer needles using SPME, J. High Resolut. Chromatogr., 18, 587 592 (1995). 

Due to its characteristic pine-needle odor, bomyl acetate is frequently used in conifer needle compositions, soap, bath products, room sprays, and pharmaceutical products. 

We investigated a number of systems in the laboratory to determine how best to size droplets on conifer needles. It soon became obvious that, from a technical point of view, dyes provided the simplest means however, we found that oil soluble dyes are... 

Schreiber, L., Schonherr, J. (1992) Uptake of organic chemicals in conifer needles Surface adsorption and permeability of cuticles. Environ. Sci. Technol. 26, 153-159. 

Goni, M.A., and Hedges, J.I. (1990c) The diagenetic behavior of cutin acids in buried conifer needles and sediments from a coastal marine environment. Geochim. Cosmochim. Acta 54, 3083-3093. 

Conifer needles also contain volatile products which are mainly composed of mono- and sesquiterpenoids. The volatile turpentine constituents are used in the production of flavors and perfumes and in various technical and pharmaceutical products. The turpentine and rosin production of trees can be increased considerably by injecting suspensions of pitch canker fungus or chemicals such as "paraquat" (1,r-dimethyl-4,4 -bipyridinium salt) which has been found to be very effective. 

We next consider some representative values for the conductances encountered by water vapor as it diffuses out of leaves. For crop plants such as beet, spinach, tomato, and pea, gja is usually 1600 to 4000 mmol m-2 s-1, and for open stomata g usually ranges from 200 to 800 mmol mT2 s-1. Both conductances can be somewhat lower for other crops, but the maximum g f is still 80 to 400 mmol m-2 s-1 for most cultivated plants. Compared to crop plants, the maximum g f is usually lower for leaves of deciduous trees and conifer needles (see Table 8-1). As the stomata close, g,s, and hence g f decrease accordingly. The minimum value for leaf water vapor conductance occurs for fully closed stomata and essentially equals the cuticular conductance (see Eq. 8.14). Measured values of g, vary considerably, in part... 

Deciduous Conifer needle Grass leaf Grass root Deciduous Bacteria Fungi leaf Finns D. flexuosa Loudetia wood... 

In spite of the finding that aqueous solutions of 2,4-DNP quickly permeate plant cuticles and probably metabolize fast in plants, this chemical has been detected in conifer needles. Concentrations of 2,4-DNP in the needles collected from different areas and of different ages ranged from <3.7 to 33.1 pg/kg (Hinkel et al. 1989). The concentrations of 2,4-DNP were higher in needles obtained from roadside and urban areas than rural areas. The higher concentrations of... 

Hinkel M, Reischl A, Schramm KW, et al. 1989. Concentration levels of nitrated phenols in conifer needles. Chemosphere 18 2433-2439. 

Gordon, C.C. 1972. Short-long conifer needle syndrome. 

Isobilateral dicot leaves, conifer needles, and many monocot leaves, receive light on both surfaces. The light response curves of photosynthesis of such leaves have sharper transition when the leaves are irradiated from both sides simultaneously than when irradiated unilaterally (18-20). This may also be ascribed to the differentiation of tissues in terms of optical properties and the gradient in properties of chloroplasts. Thus, it can be generalised that the leaf is constructed so as to maximise the sharpness of the transient region under natural light conditions. 

Schales, C., H. Gerlach, and Kosters, J., 1993. Investigations on the antibacterial effect of conifer needle oils on bacteria isolated from the feces of captive Capercaillies Tetrao urogallus L., 1758). J. Veter. Med. Ser. B, 40 381 390. 

There is less knowledge of the responses of diterpenes to changing temperature. However, the evidence of resin acid concentrations of conifer needles and bark at... 

Vitamin C is widely distributed in nature, especially in green vegetables and citrus fruits. It has been found in conifer needles, and its presence in the lowly potato provides an excellent dietary source for those unable to secure other foods. It is universally distributed in plant tissues, normally in the... 

Linder W, Grill D 1978 Acids in conifer needles. Phyton (Horn, Australia) 18 137-144... 

Clark, C.L., J.D. Miller N.J. Whitney. 1989. Toxicity of conifer needle endophytes to spruce budworm. Mycol. Res. 93 508-512. 

Innes, J.L. and Boswell, R.C. (1989b). Sulphur contents of conifer needles in Great Britain. GeoJournal 19, 63-66. 

NIHLGARD B., ( 1989). Nutrients and structural dynamics of conifer needles in South Sweden 1985-1987. MeddNor, inst. skogforsk. 42(1) 157-165. 

Dormant western white pine is, along with lodgepole pine, one of the more cold-hardy western North American conifers. Needle desiccation can result from winds or sun causing excessive moisture loss during times when soil is frozen or cold. Western white pine is quite tolerant of heat compared to... 

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