Normal
0
false
false
false
EN-US
X-NONE
X-NONE
MicrosoftInternetExplorer4
/* Style Definitions */
table.MsoNormalTable
{mso-style-name:”Table Normal”;
mso-tstyle-rowband-size:0;
mso-tstyle-colband-size:0;
mso-style-noshow:yes;
mso-style-priority:99;
mso-style-qformat:yes;
mso-style-parent:””;
mso-padding-alt:0in 5.4pt 0in 5.4pt;
mso-para-margin:0in;
mso-para-margin-bottom:.0001pt;
mso-pagination:widow-orphan;
font-size:11.0pt;
font-family:”Calibri”,”sans-serif”;
mso-ascii-font-family:Calibri;
mso-ascii-theme-font:minor-latin;
mso-fareast-font-family:”Times New Roman”;
mso-fareast-theme-font:minor-fareast;
mso-hansi-font-family:Calibri;
mso-hansi-theme-font:minor-latin;
mso-bidi-font-family:”Times New Roman”;
mso-bidi-theme-font:minor-bidi;}
important uses of fire in restoration ecology . It is important to understand
that in most situations fire does not actually “kill” invasive shrubs. What it
does is kill the cambium layer and associated xylem and phloem, thus preventing
vertical transport between the stems and the roots. This effect is analogous to
girdling.
root collar region of most hardwood trees and all shrubs are living dormant
buds whose growth is suppressed by hormones coming from the stems. With the plant’s
vertical transport system destroyed, the hormone supply to the roots is gone, so
one or more of the dormant buds in the root collar is released.
a shrub but does not get rid of it, because it will resprout from the base.
The lethal temperature of the cambium layer
of woody plants is about 70-75 C. Fire, of course, is much hotter than that.
Grass fires produce temperatures of 400-500 C or hotter and oak leaves burn at
about 200 C. (See this link for oak leaf temperature measurements.)
Normal
0
false
false
false
EN-US
X-NONE
X-NONE
MicrosoftInternetExplorer4
/* Style Definitions */
table.MsoNormalTable
{mso-style-name:”Table Normal”;
mso-tstyle-rowband-size:0;
mso-tstyle-colband-size:0;
mso-style-noshow:yes;
mso-style-priority:99;
mso-style-qformat:yes;
mso-style-parent:””;
mso-padding-alt:0in 5.4pt 0in 5.4pt;
mso-para-margin:0in;
mso-para-margin-bottom:.0001pt;
mso-pagination:widow-orphan;
font-size:11.0pt;
font-family:”Calibri”,”sans-serif”;
mso-ascii-font-family:Calibri;
mso-ascii-theme-font:minor-latin;
mso-fareast-font-family:”Times New Roman”;
mso-fareast-theme-font:minor-fareast;
mso-hansi-font-family:Calibri;
mso-hansi-theme-font:minor-latin;
mso-bidi-font-family:”Times New Roman”;
mso-bidi-theme-font:minor-bidi;}
enough to kill the stems of any shrub it passes near. The dormant buds in the
root collar, now released from hormonal inhibition, grow. Thus, fire cannot eradicate
well-established invasive shrubs.
 |
| Typical low-intensity fire line with oak leaves fuel |
 |
| Patch of woody shrubs after the fire has moved through |
An understanding of how fire works offers a convincing case
that herbicide use is essential to eradicate invasive shrubs. Fire and
herbicide act as collaborative agents
in the eradication of invasive woody plants. Although herbicide can be used
without fire, it is much easier to kill shrubs after they have experienced
fire. The small resprouts that arise from the top-killed shrubs are excellent
targets for herbicide. A spring fire will set the stage for spraying.
native spring vegetation is small or still underground, and the shrub resprouts
are also small and can easily be found.
 |
|
| Buckthorn resprouts in a burned area. There are at least 3 shoots, each from a dormant bud |
option. If a site is burned annually, the shrubs will be top-killed annually and
should never be able to become dominant again. However, in this situation, you
can’t miss a year.
actually eradicate woody plants. Newly grown shrub seedlings are killed by
fire. This is because they have not had time to make a substantial root system,
so dormant buds are not present. Thus, one might be able to eradicate a patch
of buckthorn seedlings with fire (prescribed burn or a propane torch). However,
in most restorations, the invasive shrubs are well past the seedling stage.