Post-fire seeding

A quick note about seeding, particularly of non-native, often invasive plants after fires.

It’s a bad idea. A really, really bad idea.

Even with natives, I’m not sure that dumping seeds across large areas is a great idea in this context. It will probably dramatically change the species composition of the area in the short term (effectively prolonging the disturbance created by the fire) and might do so in the long term. It has risks that we do not understand.

So, that aside, the risk of dumping non-natives into an area is more obvious. We risk replacing our spectacular native flora with a depauperate one. We risk permanently preventing an area from recovering from a fire. In this case, the fire isn’t the problem. What we do afterwards is the problem. A fire is a temporary disturbance, but an established invasive species is a permanent disturbance.

Unfortunately, post-fire seeding with non-native species remains common. A recent example is the Silver Fire (2013) in the Black Range. It was seeded with Hordeum vulgare, Triticum aestivum, and perhaps various other contaminants. The Hordeum and Triticum probably will not persist. Hopefully this will just be a severe, but temporary, disruption of post-fire succession. But… well, we don’t know. This is a bad idea.

After the Peppin Fire (2004) in the Capitan Mountains, the area was seeded with Psathyrostachys juncea. I first noticed this species in profusion back in 2006. I hoped it was temporary. I visited the area again a few weeks ago. It is still there and abundant, now 10 years on from the fire. At this point, I think it is likely it will be there indefinitely and that this represents a permanent replacement of part of the native flora with an invasive species. This seeding was an extremely bad idea. We should not have allowed this to happen.

Also, both areas contain a number of rare species. For instance, in the Capitan Mountains, the seeded area includes the rare species: Cirsium inornatum, Erigeron rybius, Lupinus sierra-blancae, Geranium dodecatheoides, Penstemon cardinalis, Penstemon neomexicanus, Eriogonum wootonii, Delphinium novomexicanum, Heuchera woodsiaphila, and Heuchera wootonii. There are probably several others. Those are just the rare plants I am certain of because I have seen them there! Why would you introduce an invasive species into an area with a wealth of rare species? We don’t know if Psathyrostachys juncea will have deleterious effects on all or none of these in the long term. But why take that risk?

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