Skip to page content
USDA Forest Service
  
Treesearch

Research & Development Treesearch

 
Treesearch Home
About Treesearch
Contact Us
Research & Development
Forest Products Lab
International Institute of Tropical Forestry
Northern
Pacific Northwest
Pacific Southwest
Rocky Mountain
Southern Research Station
Help
 

Science.gov - We Participate


USA.gov  Government Made Easy


Global Forest Information Service

US Forest Service
P.O. Box 96090
Washington, D.C.
20090-6090

(202) 205-8333

You are here: Home / Search / Publication Information
Bookmark and Share

Publication Information

View PDF (383.0 KB bytes)

Title: How oaks respond to water limitation

Author: Allen, Michael F.;

Date: 2015

Source: Gen. Tech. Rep. PSW-GTR-251. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station: 13-22

Publication Series: General Technical Report (GTR)

   Note: This article is part of a larger document. View the larger document

Description: Oaks are extremely resilient trees. They have persisted since the mid-Cretaceous, with life forms ranging from shrubs to large trees, from evergreen to deciduous. They have two distinct, but critical, adaptations to drought that make this "mesic" taxon adaptable to dry hot environments. First, they form both arbuscular and ectotrophic mycorrhizae, with a high diversity of fungi that independently evolved many times. This means that a single tree forms mycorrhizal symbioses with partners adapting to different conditions and accessing many different resources. Oaks also have deep roots. This allows access to water resources deep in the groundwater, and with hyphae that extend into the granite matrix. Thus, water can be accessed even during drought periods when surface soils are extremely dry. Fine roots and mycorrhizal hyphae persist utilizing hydraulically-lifted water, and can even take up nutrients during these extremely dry conditions. These mycorrhizal hyphae remain viable during drought periods allowing them to rapidly utilize surface precipitation from summer monsoonal events. Together, these adaptations should allow oaks to persist and even thrive under the projected climate change, unless conditions become too harsh. That remains a critical task of future research and monitoring.

Keywords: anthropocene, drought, mycorrhiza, nitrogen, nutrient, oak, root

Publication Notes:

  • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
  • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.

XML: View XML

Citation:


Allen, Michael F. 2015. How oaks respond to water limitation. In: Standiford, Richard B.; Purcell, Kathryn L., tech. cords. Proceedings of the seventh California oak symposium: managing oak woodlands in a dynamic world. Gen. Tech. Rep. PSW-GTR-251. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station: 13-22.

 


 [ Get Acrobat ]  Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility

USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.