Does Baccharis conferta Shrub Act as a Nurse Plant to the Abies religiosa Seedling?

ABSTRACT

The role played by nurse plants represents a common ecological process in nature; this being an interaction where a particular species benefits from the presence of another species. Nurse plant species offer an efficient aid for the survival and growth of other species, including some which are of economic importance or interest for conservation. Baccharis conferta Kunth (shrub) and Abies religiosa (tree) are two common species which cohabit in the mountains of Mexico. It is general a practice, when establishing plantations to clear the mountainside, which involves cutting down and removing all shrubs. In order to discover whether B. conferta acts as a nurse plant when Abies religiosa seedlings are becoming established, this research evaluated the effect of this plant on the survival and growth of Abies religiosa seedlings. After taking records for two years, we found that the survival of A. religiosa did not vary significantly under the two contrasting conditions (65% with B. conferta and 55 % without B. conferta, nor was there significant interaction among years, contrasting conditions and experimental plots (G2 = 0.01, P> 0.91). However, height and coverage were significantly greater under the B. conferta canopy ((t = 3614, P < 0.001 and t = 2910, P < 0.001, respectively) than without B. conferta, but not in terms of the stem base diameter (t = 0.689, P > 0.49). We concluded that B. conferta promotes the seedling growth of A. religiosa, reducing costs for commercial plantations or plantations aimed towards restoration.