Canopy architecture of <i>Larrea tridentata</i> (D. C.) Cov., a desert shrub: foliage orientation and direct beam radiation interception

TitleCanopy architecture of Larrea tridentata (D. C.) Cov., a desert shrub: foliage orientation and direct beam radiation interception
Publication TypeJournal Article
Year of Publication1988
AuthorsNeufeld HS, Meinzer FC, Wisdom CS, M. Sharifi R, Rundel PW, Neufeld MS, Goldring Y, Cunningham GL
JournalOecologia (Berlin)
Volume75
Pagination54-60
Date Published1988
Call Number00242
Keywordsarticle, articles, journal, journals, Larrea,canopy architecture, Larrea,leaf orientation, Larrea,light interception
AbstractAt sites in the United States, creosote bushes (Larrea tridentata (DC.) Cov.) orient foliage clusters predominantly toward the southeast . Foliage of bushes at the southernmost distribution extreme in Mexico shows no predominant orientation. Clusters at all sites are inclined between 33 degrees and 71 degrees form the horizontal. Inclinations are steeper in the drier and hotter Mojave Desert than in the Chihuahuan Desert. Individual leaflets, though not measured, appear more randomly oriented than foliage clusters. In several populations studied, branches were shorter in the southeastern sectors of the crown, reducing self-shading early in the morning. Measurements of direct beam radiation interception by detached branches, using digital image processing, indicated that foliage clusters oriented toward the southeast exhibited less self-shading during spring mornings than clusters oriented northeast. This effect was not apparent at the summer solstice. This type of canopy architecture may tend to minimize self-shading during the morning hours when conditions are more favorable for photosynthesis, resulting in an improved daily water use efficiency.