P Elliottii X P Caribaea Case Study
Background
P. elliottii x P. caribaea is a fast growing tree, with a good stem form and good branching characteristics. The hybrid produces a stable wood with mature wood properties comparable to or better than those of commercial species such as P. patula, P. elliottii and P. taeda. (Malan, 2002). Both the parent species used to create this hybrid unfortunately are known to from resin-related defects. It is thus expected that this hybrid suffers from the same resin related defects and there appear to be some site effect that influence the formation of resin defects.
Studies indicated that resin infiltration in the form of streaks and/or broad bands in the pith area are a problem in the tree stem of this hybrid. While P. elliottii –like shakes …show more content…
These rings had a high proportion of earlywood and consequently wood of comparatively low density. The ring structure of the trees taken from the Dukuduku trial, on the other hand, exhibited well-defined rings across the entire radius, together with numerous false rings. Resin tails extending upwards and downwards from the knot is a common feature in P. caribaea and were quite common in the Dukuduku material as well (Malan, 1994, 1995). When present they occurred above as well as below the knot and were generally longer on the upper side (Figure 4). None of the trees taken from the trial at Dukuduku showed any sign of resin …show more content…
However, the impact of resin-associated defects can be quite pronounced pronounced. More than 30% of the boards produced by the trees sampled from a Dukuduku trial were adversely affected by streaks of resin running upwards and downwards from knots. Severe resin infiltration also occurres in the core of some trees. In some areas resin shakes can affect up to 26% of the trees with downgraded boards of up to 10% due to the presence of resin shakes.
References
Malan, F.S., 2000 The wood quality of Pinus elliottii Emgelm. x P. caribaea. Internal Company Report, South African Forestry Company Ltd (SAFCOL).
Malan, F.S., 2002 The wood properties of Pinus elliottii Emgelm. x P. caribaea grown in South Africa, with special reference to results obtained from a 29-year-old trial in KwaZulu Natal. Company Report, South African Forestry Company Ltd (SAFCOL).
Malan, F.S., 2013 Family, growth rate and site effects on the growth and wood stiffness of five-year-old South African P. elliottii x P. caribaea. Company Report, South African Forestry Company Ltd (SAFCOL).
Wessels CB, Dowse GP and Smit HC (2011) The flexural properties of young Pinus elliottii x Pinus caribaea var hondurensis timber from the Southern Cape, and their prediction from acoustic measurements. Accepted: Southern Forests: A Journal of Forest
P. elliottii x P. caribaea is a fast growing tree, with a good stem form and good branching characteristics. The hybrid produces a stable wood with mature wood properties comparable to or better than those of commercial species such as P. patula, P. elliottii and P. taeda. (Malan, 2002). Both the parent species used to create this hybrid unfortunately are known to from resin-related defects. It is thus expected that this hybrid suffers from the same resin related defects and there appear to be some site effect that influence the formation of resin defects.
Studies indicated that resin infiltration in the form of streaks and/or broad bands in the pith area are a problem in the tree stem of this hybrid. While P. elliottii –like shakes …show more content…
These rings had a high proportion of earlywood and consequently wood of comparatively low density. The ring structure of the trees taken from the Dukuduku trial, on the other hand, exhibited well-defined rings across the entire radius, together with numerous false rings. Resin tails extending upwards and downwards from the knot is a common feature in P. caribaea and were quite common in the Dukuduku material as well (Malan, 1994, 1995). When present they occurred above as well as below the knot and were generally longer on the upper side (Figure 4). None of the trees taken from the trial at Dukuduku showed any sign of resin …show more content…
However, the impact of resin-associated defects can be quite pronounced pronounced. More than 30% of the boards produced by the trees sampled from a Dukuduku trial were adversely affected by streaks of resin running upwards and downwards from knots. Severe resin infiltration also occurres in the core of some trees. In some areas resin shakes can affect up to 26% of the trees with downgraded boards of up to 10% due to the presence of resin shakes.
References
Malan, F.S., 2000 The wood quality of Pinus elliottii Emgelm. x P. caribaea. Internal Company Report, South African Forestry Company Ltd (SAFCOL).
Malan, F.S., 2002 The wood properties of Pinus elliottii Emgelm. x P. caribaea grown in South Africa, with special reference to results obtained from a 29-year-old trial in KwaZulu Natal. Company Report, South African Forestry Company Ltd (SAFCOL).
Malan, F.S., 2013 Family, growth rate and site effects on the growth and wood stiffness of five-year-old South African P. elliottii x P. caribaea. Company Report, South African Forestry Company Ltd (SAFCOL).
Wessels CB, Dowse GP and Smit HC (2011) The flexural properties of young Pinus elliottii x Pinus caribaea var hondurensis timber from the Southern Cape, and their prediction from acoustic measurements. Accepted: Southern Forests: A Journal of Forest