Sunday

Rubber Rabbitbrush

The landscape restoration efforts at the Painted Pony Resort continue and new challenges constantly arise.  One of these revolves around the idea of succession, that the desert plant communities on the estate are in flux either as a result of changes in climate or more directly the result of past human activity.  The idea of secondary succession in restoring the grasslands had not occurred until a close examination of the test restoration area showed a majority of woody shrubs.  In areas where all the topsoil was lost, Rubber Rabbitbrush, Ericameria nauseosa, is one of the species that first covers the area as topsoil is rebuilt.  In areas around buildings where this species has colonized and was later removed have now returned to grasses supporting the notion that plant community succession is occurring in areas where active restoration activity is occurring.  Previous work at the Portal Project suggested in a paper that a landscape wide reorganization was occurring as a result of climatic changes.  Specifically increased winter moisture which favors the production of cool season active C3 shrubs at the expense of warm weather C4 grasses was responsible for changes observed in their fenced test plots.  So there seems to be 2 alternatives with respect to the appearance of  Rubber Rabbitbrush, either it is symptomatic of a reorganization or that its appearance is related to active landscape management and is part of the natural succession that accompanies landscape restoration on the estate.

Rubber Rabbitbrush rapidly colonizes burned areas and is useful in preventing soil erosion.  Its' woody stems contain a natural rubber compound, hence the common name, but is not economically viable as a rubber source.  Nor is it particularly useful as forage but does provide pollinators a late summer source of nectar and cover for birds and mammals. Another useful feature is that it does not compete well with native grasses and over time will be replaced through competition.  While the density of Rubber Rabbitbrush varies across the landscape it seems to do best (the largest stands) where water collects suggesting it has a higher moisture requirements when compared with native grasses.

pre-monsoon view showing protected versus grazed land.  Note the quantity of Rubber Rabbitbrush in ungrazed areas.


Rubber Rabbitbrush

Rubber Rabbitbrush in bloom, note the small yellow flowers

Stand of Rubber Rabbitbrush around a grey water drain.

4 comments:

  1. huh, "rubber rabbitbrush" is a new name to me! Thanks!

    ReplyDelete
  2. Yes, it is a funny name, but seems to be everywhere. In a couple of places I have chopped it out and grass (annual) came back in its place, but I'm still not sure if it is a sign of succession or reorganization and I'm not sure how to test the idea.

    ReplyDelete
  3. I've pulled out some of the rubber rabbitbrush here but never knew its name. It pulls out easier than other things. All this rain makes for a "jungle yard"

    ReplyDelete
  4. I have heard that this is a particularly active growing year from others and the valley is quite green this year. I've also found a sharp shovel makes quick work of the rubber rabbitbrush when trying to get rid of it.

    ReplyDelete