A better understanding of woody plant ecology is necessary in order to develop more effective and sustainable brush management strategies. Ecological studies that our lab has been involved in include:
- mesquite seed ecology
- mesquite water use and photosynthesis rates
- mesquite competition with understory grasses
- mesquite root growth during droughts
- mesquite leaf area and LAI dynamics
- mesquite and juniper biomass production
- mesquite regrowth dynamics
Our research has found that a 3 meter tall, multi-stemmed mesquite tree can use 20-80 liters (5-20 gallons) of water per day during mid-summer. Mesquite leaf area indices (LAI) are generally between 1 and 1.8, but rarely over 2. Trees will shed some leaves during summer drought and show drought stress when lateral roots are severed. Thus, the mesquite in this region of Texas are not totally phreatophytic. Total leaf mass comprises about 8-12% of total oven dry tree mass.
Mesquite in dense stands (>25% cover) can reduce grass growth by as much as 50-80%, yet lighter densities of mesquite (<15% cover) either have no effect or can sometimes enhance grass growth. Many animals, including cattle, consume mesquite seeds and re-distribute those seeds though their feces. This can greatly accelerate rates of brush encroachment. Our studies have also found that mesquite greatly accelerates root growth during drought.