Search results
Results From The WOW.Com Content Network
Most of the breeding efforts for five-needle pine resistance are currently focused in North America, on P. strobus, P. monticola and P. lambertiana. [18] The means of resistance in rust-resistant five-needle pine varieties involve various mechanisms, such as abortion of infected leaves and slow development of canker symptoms. [7]
An elongated white scale insect, the pine needle scale feeds on the needles causing fluffy white patches on the twigs and aphids also suck sap from the needles and may cause them to fall and possibly dieback. Mites can also infest the blue spruce, especially in a dry summer, causing yellowing of the oldest needles.
The most infected needles are prematurely shed by December. Because the infected needles are within the interior of the tree, the newer needles on the outer surface of the pines are flushed green and resistant to the disease. However, the premature shedding of needles in the interior can extend outwards leading to a loss in overall growth.
For premium support please call: 800-290-4726 more ways to reach us more ways to reach us
P. schweinitzii is a polypore, although unlike bracket fungi the fruiting body may appear terrestrial [citation needed] when growing from the roots or base of the host tree. [2] The fruiting bodies, appearing in late summer or fall, commonly incorporate blades of grass, twigs, or fallen pine needles as they grow. [3]
Pinus pungens is a tree of modest size (6–12 metres or 20–39 feet), and has a rounded, irregular shape. The needles are in bundles of two, occasionally three, yellow-green to mid green, fairly stout, and 4–7 centimetres (1 + 1 ⁄ 2 –3 in) long. The pollen is released early compared to other pines in the area which minimizes hybridization.
This fungal disease affects the needles of conifers, but is mainly found on pine. Over 60 species have been reported to be prone to infection and Corsican Pine (Pinus nigra ssp. laricio) is the most susceptible species in Great Britain. [3] It was first recorded in Britain on Corsican pine in 1954 in a nursery in Dorset.
The tree produces spiky green fruits about the size of a golf ball, which turn brown and drop off the tree over an extended period beginning in fall and continuing over the winter.