Old Pinus ponderosa growth responses to restoration treatments, climate and drought in a southwestern US landscape

Chris C. Erickson, Kristen M Waring

Research output: Contribution to journalArticle

5 Scopus citations


Questions: Do landscape-scale thin and burn restoration treatments have a long-term, landscape-scale impact on old Pinus ponderosa growth? Is there a relationship between old P. ponderosa growth and climatic factors, in particular, drought, before and after restoration treatments? Location: Northwestern Arizona, USA. Methods: We looked at old P. ponderosa growth across the landscape in both an area 'treated' by thin and burn restoration treatments, and a neighbouring untreated area. We re-visited each old P. ponderosa located on permanent 0.1-ha plots installed across the landscape prior to treatment implementation and recorded tree status, diameter, aspect, slope and competition from neighbouring trees. Growth was analysed from shallow increment cores taken from each tree at breast height (1.37 m). Comparisons of growth between the treated and untreated areas were carried out using regional proxy and instrumental Palmer drought severity index values and instrument precipitation data. Results: We found significant differences in precipitation and temperature between the treated and untreated areas, indicating a drier, less advantageous climate in the untreated area. Old trees in the treated area responded less negatively in diameter growth to treatments; both treatment and abiotic site factors were important in predicting post-treatment growth. All old trees grew slowly during drought years; however, old trees in the treated area grew better after three recent drought years than old trees in the untreated area. Conclusions: Old P. ponderosa diameter growth increased following restoration, though not immediately. Old trees in the treated area also grew better in the years after drought than old trees in the untreated area. Restoration, or similar treatments removing small, neighbouring trees may be critical in maintaining old P. ponderosa in the landscape, particularly under future climate change and increasing drought frequency in the western USA.

Original languageEnglish (US)
Pages (from-to)97-108
Number of pages12
JournalApplied Vegetation Science
Issue number1
StatePublished - Jan 2014



  • Climate change
  • Competition
  • Drought
  • Old growth
  • Ponderosa pine
  • Restoration
  • Southwest USA
  • Thin and burn treatments
  • Treatment effects

ASJC Scopus subject areas

  • Management, Monitoring, Policy and Law
  • Nature and Landscape Conservation
  • Ecology

Cite this