Vegetative growth response of Cytisus oromediterraneus to fuel reduction treatments

Abstract

Studies of the effects of fuel reduction treatments on the recovery of shrubland communities have increased substantially in recent years. However, the effects on the resprouting response of shrubs have been less well studied, even though such information would help land managers select the most appropriate treatment. Cytisus oromediterraneus Riv. Mart. is a species characteristic of the Mediterranean basin, where it occupies a vast area of the terrain. It is a facultative resprouter and can thus regenerate asexually, although little is known about its response to prescribed fire or mechanical treatments. In this study, we evaluated the resprouting ability of this species during the first 2 years after the application of prescribed burning and two different types of mechanical treatments (clearing and mastication). Plant mortality after the treatments was low and did not differ between treatments. The number of resprouted shoots was higher after clearing than after both prescribed burning and mastication, but did not differ between the latter two treatments. Most of the shoots are in ramets originated from the rootstocks. The pre-treatment plant size favored the plant resprouting response after fuel reduction treatments. The minimum stem diameter and plant height, proxy measures of treatment severity, were not related to the number of resprouted shoots. The degree of soil compaction after treatments negatively affected the C. oromediterraneus resprouting response. The number of resprouted shoots of C. oromediterraneus was not affected by any of the thermal parameters, indicating its resilience to fire.