Predictive equations for leaf area and biomass for sugar bushes in eastern Ontario

Abstract

In January 1998, an extensive ice storm caused severe damage to sugar bushes in Eastern Ontario. Foliage biomass and foliage area estimates were required to assess effects of the ice storm and remedial treatments on variables related to sugar maple production. Equations were developed to predict leaf biomass of undamaged individual sugar maple trees in the ice-damaged area. The data were collected in early to mid-August 2000 in eastern Ontario. Basal diameter of all third-order branches of 22 trees from two stands was measured, along with tree DBH, total height, and height to the base of live crown. In addition, foliage was collected from two branches (one from the lower and one from the upper part of each tree's crown). Samples were used to develop equations predicting leaf biomass (ovendried weight) of individual branches from their basal diameter. These equations were applied to estimate total leaf biomass of individual trees, and the resulting estimates were used to develop equations predicting leaf biomass from DBH and the number of branches per tree. Tne resulting equations accounted for over 90% of the variation in leaf biomass of individual trees. Leaf biomass-DBH equations for the two stands were significantly different (P < 0.0001), while no significant difference was detected in the leaf biomass-number of branches equations (P = 0.1573) for the two stands.Key words: allometric equation, branch basal diameter, DBH, ice damage, leaf area, leaf biomass, sugar maple (Acer saccharum Marsh.)En janvier 1998, une forte tempcte de verglas a caust des dommages importants aux Crablikres de l'est de I'Ontario. Les estimts de la biomasse et de la surface foliaire Ctaient requis pour Cvaluer les effets de la tempcte de verglas et identifier les traitements correctifs en fonction des variables relikes B la production acCricole. Des Cquations ont Ct C dCveloppCes pour prCdire la biomasse de chaque Crable B sucre endommag6 dans la zone sinistrke. Les donnees ont Ct C recueillies entre le dCbut et la mi-aoGt 2000 dans I'est de l'ontario. Le diamktre prks du tronc des branches tertiaires de 22 arbres rCpartis dans deux peuplements a Ct C mesure, ainsi que le dhp de l'arbre, sa hauteur totale et la distance entre le sol et le dCbut de la cime verte. De plus, le feuillage a Ctt recueilli sur deux branches (l'une situCe dans la partie infkrieure et I'autre dans la partie suptrieure de la cime de chacun des arbres). Des tchantillons ont Ct C utilisCs pour Claborer des Cquations de prediction de la biomasse foliaire (poids sec au four) de chaque branche B partir de leur diamktre prks du tronc. Ces Cquations ont kt6 utilisCes pour estirner la biomasse foliaire totale de chaque arbre, et les rCsultats obtenus ont semi B 1'Claboration d'kquations de prediction de la biomasse foliaire 2 partir du dhp et du nombre de branches par arbre. Les Cquations ainsi obtenues tenaient compte de 90 % des cas de variation de la biomasse foliaire de chaque arbre. Les Cquations de biomasse foliaire en fonction du dhp pour les deux peuplements C...

Leaf area index change in ice-storm-damaged sugar maple stands

“…Indicators at the individual leaf or branch levels typically include measures of plant physiological stress using direct (e.g., leaf chemistry) or indirect (e.g., chlorophyll fluorescence) methods (Sampson et a1.2000). At the tree scale, indicators measure structural or crown productivity parameters such as percentage crown loss, decrease in crown closure, branches remaining (Lautenschlager and Winters 2001) or foliar biomass (Ter-Mikaelian and Lautenschlager 2001). These are often aggregated over several samples to form an area-(plot-) based measure.…”

Quantifying ice damage by counting branches on damaged sugar maple trees

“…However, ground-based branch counters were instructed to count third-order branches that were 5.0 cm or larger while, to better document foliar biomass, the tree-based branch counter recorded branches that were between 2.5 to 5.0 cm (Ter-Mikaelian and Lautenschlager 2001).…”