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Comment by chasil | Hacker News Reader

It is well-known that morel mushrooms do very well in a freshly-burned forest.

"...black morels (Morchella elata and related species) are mostly found in coniferous forests, disturbed ground and recently burned areas."

https://en.wikipedia.org/wiki/Morchella

https://en.wikipedia.org/wiki/Morchella#Association_with_wil...

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"Do very well" may not be quite correct. When mycorrhizal hosts die, the organism puts all its energy into escaping the dead end - fruiting and dispersing spores. If there are periodic fires that kill trees, that's a great time to spread to a neighboring area. If giant fire that takes out vast areas, that may be less good.

But controlled burns and fires that otherwise do not cause complete incineration of the symbiotic trees/plants would not result in the death of the fungi. However, with the ground cleared, the spores would travel further.

There are also fire-dependent plants that are reproduction-adapted for these conditions.

"Some cones, such as those of lodgepole pine and sequoia, are pyriscent, as well as many chaparral shrubs, meaning they require heat from fire to open cones to disperse seeds."

https://en.wikipedia.org/wiki/Controlled_burn

Yes, it's an adaptation for a particular ecosystem.

Most california sages also require the presence of ashes to germinate. It's quite common amongst flora in the California chaparral. In large part due to thousands of years of ecosystem management with controlled burns by native Californians. In a lot of ways California is a manufactured landscape (though even Amazonia has been labelled as manufactured[0] so it's not all that surprising)

[0] https://www.researchgate.net/publication/259126195_Dark_eart...

I'm not sure if that is quite accurate although it is plausible given the negative effect of hotter fires in traditionally fire controlled areas. I read into this a couple years ago and found published data on increased harvests of morels in terms of kg/hectare after large forest fires [example from looking again today 1]. I think as humans we are biased to think above the ground and think of destruction.

There could be a a difference due to an intensely hot fire in an area where fires have been historically suppressed. There is a survey of pickers on whether hotter fires are more or less productive with 29% vs 54% [2] but I don't know the methadology.

[1] 'Approximately 250 000 ha of British Columbia forest lands were burnt (Filmon 2004). In the East Kootenay region alone, a total of 43 679 ha burned that year. Based on this figure, the apparent correlation of morel production with recent wildfire exposure, and the morel production levels observed in random experimental plots (7568 morels per hectare), Keefer (2005) estimated that 76 × 107 kg ascocarps grew in the region in 2003. Assuming the average weight of morels harvested in the region matches the 20 g per ascocarp observed by Pilz et al. (2004) in the United States, this would amount to 2.27 × 107 kg of morels produced in the region during the first flush of 2004. The size and scope of subsequent flushes is unknown but based on observations of two additional flushes in the burnt forest at Lamb Creek (Winder and Keefer 2008), the actual size of the potential morel crop could be tripled from the above estimate' https://cdnsciencepub.com/doi/10.1139/B08-045

[2] https://central.bac-lac.gc.ca/.item?id=mr05125&op=pdf&app=Li...

Do those studies look long term though? Increased harvests is exactly what you'd expect from the phenomenon I described.

That's a good point. I'm not sure. Some areas I pick edible mushrooms other that morels have not recovered from logging or fires short or long term so my individual anecdotal experience is no. I couldn't find good data on chanterelles or boletus species.

I don't think morels are entirely reliant on myccorrhizal relationships. There have apparently been successful small scale farming attempts without trees, check out the Danish Morel Project.

Either way, if hosts dying was all there was to it, you'd expect all sorts of myccorrhizal mushrooms to grow after a fire, and most don't.

I've definitely seen morels go crazy after their host tree dies - whether by fire or a saw. I also agree that they can likely be partially saprobes, so maybe this adaptation is related more to the latter than the former. I was just pointing out that I think it's far from settled that "fire is good for morels" is true in general, especially for mega fires.

I live on the west coast of north america - the last few years following wildfires my mum heads up to the scorched mountaintops to pick morels and sells them. Big hauls, hundreds of dollars' worth of rare mushrooms growing in ruined forests.

Perhaps the "rare mushrooms" should be left alone. Perhaps they would become less rare.

Edit: that's right folks, keep those downvotes coming for suggesting actually conserving something instead of exploiting it.

As far as I agree with the sentiment, mushrooms are the fruit-tip of the mycelium network.

I honestly don’t know if harvesting them change much. ( bare of methodically harvesting everything over a season )

We should put more effort into learning how to farm them, as they are so highly prized.

A hundred years ago, there was enormous production of truffles (fungi with underground fruiting bodies) in Europe, but all of that production was lost when they fell out of favor. They are not the most nutritious use of the land, but lost none the less.

https://en.m.wikipedia.org/wiki/Truffle

Maybe they were rare because forests didn't use to burn that often.

Some do, naturally. Otherwise, there wouldn't be so many adaptations to exploit it, thus the subject of the parent post and its linked article.

"In the wild, many trees depend on fire as a successful way to clear out the competition and release their seeds. In particular, the giant sequoia depends on fire to reproduce: the cones of the tree open after a fire releases their seeds, the fire having cleared all competing vegetation... Eucalyptus regnans or mountain ash of Australia also depends on fire but in a different fashion. They carry their seeds in capsules which can deposit at any time of the year. Being flammable, during a fire the capsules drop nearly all of their seeds and the fire consumes the eucalypt adults, but most of the seeds survive using the ash as a source of nutrients; at their rate of growth, they quickly dominate the land and a new eucalyptus forest grows."

https://en.m.wikipedia.org/wiki/Controlled_burn

They aren't really 'rare' they just can't be cultivated in captivity at a commercial scale well due to their need for a symbiotic relationship with trees as well as Morels being very picky about their fruiting triggers. I have seen people successfully 'seed' an area by making a slurry by blending molasses, water, and wild foraged morels that were subpar and letting the spores germinate with a water aerator running in the bucket and dumping the slurry in areas on their property that were favorable to Morels.

>wild foraged morels that were subpar

That sounds kind of like the opposite of how you'd want to slowly end up domesticating a lifeform, doesn't it?

subpar here can mean harvested too late to be palatable, not that the mushroom itself had anything wrong

Yeah, I meant past prime, slimy, partially eaten by slugs etc.

Mature mushrooms drop a billion spores a day and picking them doesn't harm the mycelium. They will be ok.

Picking them right, doesn't harm mycelium.

Digging them out and leaving the mycel exposed for examole, is bad. Cover them up again please.

And mushrooms need a lot of spores, because for a new mushroom, 2 spores have to come together by chance.

Mushroom picking does not impair future harvests – results of a long-term study in Switzerland [1]

[1] https://www.sciencedirect.com/science/article/abs/pii/S00063...

I knew a lady who, her and her two kids, make $1500 in a weekend. Oregon Coast range, don't remember what types. It's important to remember with all mushrooms there are only a few good days a year.

WA picked them near Crystal last year. This year it'll probably be near Index. The forest service provides burn maps.

PNW Mushrooms FB group for more info. Here are all the rules on commercial, personal harvesting and maps: https://www.fs.usda.gov/detailfull/okawen/passes-permits/for...

I visited a burned forest last spring, hoping to catch this phenomenon. I had been scouring the newspapers for news about small forest fires; since I live in one of the soggiest places on earth outside the tropics it doesn't happen a lot.

Didn't find any, but maybe it was too fresh (fire was in January I think, I visited late in spring). Did take some pictures. It will be interesting to compare them to what it looks like today, I plan to go there again when morel season starts. Fire ecology is fascinating in its own right... but morels, man.

Yes morel hunting is a different type of mushroom hunting than typical. In places that aren't as cold it's even a totally different season. I wouldn't be surprised if the biggest buyers of burn maps are actually morel hunters

Worth noting there's a ton of different mushrooms called morels (though they're all pretty much related and even "false morels" are usually choice edibles) and when talking about the kinds that grow after fires they're usually referred to as "burn morels"

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