succession

Treatment longevity and changes in surface fuel loads after pinyon–juniper mastication

To burn or not to burn: Comparing reintroducing fire with cutting an encroaching conifer for conservation of an imperiled shrub‐steppe

Long-term vegetation responses to pinyon-juniper woodland reduction treatments in Nevada

Are there sites where shrubs and perennial grasses and forbs can persist beneath closed pinyon and/or juniper canopies?

Yes and no.  Shrubs rarely persist beneath a closed tree canopy, especially sagebrush.  However, deep rooted perennial grasses have been observed to persist on sites with deep soils and where restrictive layers (e.g. clay accumulation layer called an argillic), reducing water capture and storage are absent or weakly developed.  Photos of two different pinyon-juniper sites,…

How do you determine if a site is fully occupied (stocked) by pinyon and or juniper?

The amount of lateral leader growth on understory sapling-size trees is a good indicator of understory competition between overstory trees.  Compare leader length in closed stands to trees growing in the open or at the edge of a stand or adjacent to a road. 

How do structure and composition change with succession to a dominant woodland canopy?

There is a strong inverse relationship between the tree overstory and understory including shrubs and perennial grasses and forbs. Shrubs rarely persist beneath a closed tree canopy, especially sagebrush.  However, deep rooted perennial grasses have been observed to persist where soils are moderately deep to deep and where restrictive layers (e.g. clay accumulation layer called…