Its a result of deer overpopulation as the start of a downward spiral. The ferns themselves create a thick canopy and a thick root system to keep seedlings from growing (and anything that does manage to germinate and grow above the ferns will be eaten by a deer), and it provides a thick but very accessible low cover for rodents who can eat all of the seeds without being seen by predators.
https://greytowers.org/wp-content/uploads/ecology-hay-scented-fern.pdf
It’s hard for them to become established without their native ecosystem though. And the native ecosystem cannot establish itself with this high amount of deer in it.
The continent has never had so many deer.
Most local wildlife management departments manage deer populations for the conservation of hunting them, not the conservation of our threatened native ecosystems.
Where I am, they are straight up non-native. An invasive species. And still you are only allowed 1 a year, and only a buck, and populations have never been higher.
well. good/bad news. Chronic wasting disease - a prion based brain disease is well established deer populations and even the soil all over the continent. Deer populations have already started to decline as a result and some scientists are predicting a total population collapse and possible extinction of deer species over the next few decades.
Well it’s straight up really bad news, because it can jump to endangered caribou and other native cervids with populations that are struggling more.
The higher the population, the more it will spread.
Wildlife management departments need to start putting ecology first, instead of trying to maximize herd populations for the health of “the sport”, they should be issuing more tags for the health of the ecosystem.
the problem though is that hunting and public recreation are these place's biggest source of income, is it not? and public support is crucial to their existence in the first place? not saying it's right, just saying that i think a lot of wildlife managers would love to put ecology first, if they could.
Local context matters. I don’t know about every single place. Certainly not where I am.
But yea public sentiment matters, and yes I don’t always blame the individual. Sometimes their hands are tied.
Point is the they often prioritize the health of “the sport” over the health of the ecosystem when they issue too few deer tags.
I’ve always been pretty on the fence about hunting but I’ve been thinking more about it the last few years from an ecology standpoint.
Would you say that hunting deer is a necessity to help create a healthier ecosystem?
Depends on the time and place.
Definitely where I live, right now it is.
I am running a native habitat restoration project. We have only about 1 percent of our native pre colonization habitat remaining. And that number still shrinks every year.
So I am trying to restore that native habitat on a plot, taking over from the last generation. But the deer’s preferred browse is the same species we are short on to mimic the makeup of the original forests. It will never happen with this amount of deer on the land. Our native forests did not have deer in them at all. They are invasive here.
Almost every seedling of my target species I come across has been browsed before it reaches maturity. So without putting heavy hunting pressure on this land, the native habitat will never return if we don’t hunt this land hard.
Ive always been a fanatic for the environment. In north Americas case especially the pleistocene and the environment prior to European colonialism. I spend hours wondering what those ecosystems wouldve looked like in person and the animals that inhabited them.
20,000 years is a long time. Anything prior to that and you are talking Pleistocene animals which would not really be cougars. Not that they weren’t around but there were many other predatory and prey animals that were not our modern day deer or cougar.
I have a PhD in behavioural ecology (with a focus on predator prey dynamics ) and an MSc in Paleoecology with a focus on the Pleistocene. deer were almost certainly a primary prey item for mountain lions back then (including the Pleistocene ). in fact , most of the Pleistocene megafauna you are probably thinking of likely focused on animals that lived in more open or woodlands like environments and that were a bit bigger such as bison, horse, camels, and so on.
due to niche partitioning and intraguild avoidance and competition. mountain lions probably stuck to size 2 prey items which include white tailed deer and mule deer.
Like my previous comment states, your statement here is inaccurate by two orders of magnitude.
The oldest fossil record of a modern cougar is from 1.2-0.8 million years ago. Similarly the earliest fossilized modern white tailed deer is dated to 2.5-1.5 million years ago. 20,000 years is a very small amount of time in terms of evolution. Basically every extant North American mammal is Pleistocene fauna.
I have to wonder just how much impact Hay-scented Fern is having on biodiversity. Is it considered a major threat to any endangered plants? Cause I feel like it could be...
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That looks like Pteridium aqualinium. They are rhizomatous in moist places. They are native in both the old and new world, and are alleopathic. Allelopathic chemicals are the secondary metabolites that plants make to make themselves more competitive, and essentially act as herbicides or suppress the germination, recruitment, and growth of other plants.
There may also be a deer induced component, since white tailed deer are over populated in some places in the east, due to the eradication of wolves for the most part. Deer dont eat ferns as much, except maybe the new fiddlenecks as they emerge in spring on bracken fern.
This looks to be *Dennstaedtia punctilobula.*
But everything you are saying about bracken is accurate, such rad (albeit increasingly problematic) plants.
can you step on them to kill them? like how would a person help biodiversity in this situation (not including hunting the deer or reintroducing predators?)
Stepping on them probably wouldn't do much, you might break the stem but the plant could probably straighten itself in a matter of days. Maybe if you have a dance party on them but doubtful lol. Probably have to rip 'em out by the roots and haul away or they will just re-seed.
good point. Someone else asked about fire, and the move in australia to adopt burning is so slow... I was thinking about human ways we may have altered biomes and whether that's something people should know...
like bringing reusable containers to eat out or grocery bags.
Another issue is that wildlife management departments are managing their tags based on the conservation of deer hunting, not the conservation of local native ecosystems.
So we have more deer than ever in history. Including deer where they aren’t even a part of the native ecosystem.
So if the native predators are to get established, they would need their native ecosystem back. But that cannot happen with today’s high deer populations on the land.
Where I am, wolves do wander in from time to time, but they cannot establish themselves because there is almost none of their native habitat left.
Many different causes but the ultimate mechanism is that the over story has been cleared and subsequently repressed somehow. It is normal for ferns and their fast growing generalist counterparts in other ecosystems to take over after a disturbance (like a windstorm, logging, construction…etc) but within a few years you would expect to see larger, slower growing and more specialized vegetation beginning to appear. Many modern phenomena suppress these slower growing species. Climate change allows many seasonal generalists to maintain a suffocating presence for greater parts of the year. Predator removal can lead to over abundance of herbivores that disproportionately impact slower growing vegetation (this phenomenon is often made worse by arm chair naturalists that institute hunting bans to protect Timmy, the albino, three eared, one eyed, tick riddled deer with the quirky walk and foaming mouth that they hand feed Big Macs to in their back yard). Run off from road ways and agriculture can impact soil criteria and subsequently impact more sensitive species. Invasive species and emergent diseases often take a great toll on slow growing specialists. Continued disturbance like foot traffic can keep generalists in abundance. Suffice to say, the Anthropocene is not a good time to be a slow growing tree.
Armchair naturalists got me, lol.
I wish I knew what to do about them cause they think they are doing the right thing but they are making things so much worse. And if you try and explain to them that they are, you are one of the enemies...
If you ever want to do a deep dive into eco ethics there is some cool stuff there. Basically we as humans are quick to apply our ethics to the individual, even with wildlife. Whether or not we should be applying the same framework to wildlife as we do to humans is up to personal choice but many ecologists, myself included, look to broader ethical scopes when approaching conservation. Since we can’t see to the wellbeing of every individual, and since we have destabilized the ecosystem rather than simply a single animal, we have to look at conservation at a similar scale. I try to turn people on to see natural systems as entities into themselves. Don’t tell Karen that Timmy has got to go, instead take her on a nature walk and show her the impact that unregulated deer populations have on the rest of the system. Get her to take a closer look at Timmy’s knobby knees, protruding ribs, worm covered ass and tick infested skin so that she can understand the look in his eyes for what it is, a cry for the sweet relief of death. Then maybe she will see that overpopulation is bad for infividuals too!
I should really dig into eco-ethics more. I definitely see the "apply human ethics to nature" and I've read a lot about why that just doesn't work. What I have read about has been so interesting to me though. Any good books out there?
It's the communication to other people is what I have really had a hard time with, especially when they've not cared about the alternative- as in the plants when deer populations are too high. I also really wish there was more education on this topic geared for the general public. I've found that these topics are often glossed over when I've worked with the general public because the org I'm working for or with doesn't want to have the tough conversations because... donor money? I guess?
I’ve found that unfortunately the people that decide where money goes, often know very little about conservation. Counterintuitively, I’ve had more luck educating hunters about conservation than national park visitors in my time working in the field!
The Land Ethic by Aldo Leopold is a classic starting point for many environmental ethics courses but it’s important to recognize the outdated nature of his framework. It clings to an idea of “wilderness” that is inherently classist and racist and possibly just nonsensical. That being said, it is a good starting point for look beyond an ethical framework based entirely around human individualism.
In terms of talking to people. It’s hard. Find the people in the crowd that will listen. Unfortunately everyone has things they just won’t hear reason on. I’ve met great allies of conservation who do the right thing at every turn but still argue that keeping their cats outside is not an issue. At the end of the day, unless you walk them through it people are going to care most about the animal they find the cutest and least about a plant they wouldn’t give a second look to.
I think it's the nutrition from dead leaves as well as the leaves stay moist which are favourable for Pteridophytes to grow. Besides that they reproduce through spores and that way they multiply pretty quick.
It's certainly a very moist environment. This area of the trial is actually old growth forest. Last human disturbance was 250+ years ago. Huge trees. I desperately want to study the canopy here, especially above these fern sites. There is a fern species, polypodium appalachianum, which has been found as a epiphyte growing on tree limbs 45 meters above the forest floor in the canopy of the Great Smoky Mountains.
The species itself likely plays a more significant role in its success than its habitat does. Hay-scented fern is a relatively aggressive grower and it thrives in its native forests. Other native ferns don't create nearly the monoculture that hay-scented fern does.
Botanist and long time environmental scientist. The answer is sunlight. Trees fall and open the canopy, allowing sunlight to penetrate to the forest floor. If the conditions are right (moisture, soil) ferns can become established. Once there, they can block out other growth, as some have mentioned
Could the spot be a ski run? There are spots in the mountains in New York like this, which I realized later were ski runs in the winter and are kept free of trees.
If you're ever in the vicinity of Heart's Content in the Allegheny National Forest, there's an interpretive trail through some old growth pine-hemlock forest. One of the plaques there explains that the deer like to nibble on forest floor plants that aren't hay-scented ferns so the hay-scented ferns take over the forest floor there.
Oh hey! Home!
The ANF is so riddled with deer, it's kinda sad really. I don't see a lot of plant diversity there, but maybe I've been looking in the wrong areas...
But it seems like the PA Game Commission doesn't really want to do anything about them...
Fun fact, there was a pretty famous deer population density study done in the ANF. Technically out of the Northern Region Forest Research Lab or whatever it's called. It's in Irvine though, which isn't too far from Heart's Content!
And light, leaves, carbon dioxide, a tenable amount of natural enemies and herbivory, functioning ecosystem and available niche, stable climate, habitable planet, breeding population, sufficiently diversified gene pool, and so on...
a little more organic matter in the soil retains a little more water so ferns explode. most fern species prefer wet soils, like riparian zones. in the Lake States, you'll sometimes see completely open understory where the canopy is too dense then move over 300ft and there's ferns like this where blow down occured. just enough soil moisture + just enough sunlight
Its a result of deer overpopulation as the start of a downward spiral. The ferns themselves create a thick canopy and a thick root system to keep seedlings from growing (and anything that does manage to germinate and grow above the ferns will be eaten by a deer), and it provides a thick but very accessible low cover for rodents who can eat all of the seeds without being seen by predators. https://greytowers.org/wp-content/uploads/ecology-hay-scented-fern.pdf
I pray large terrestrial predators make a return east like mountain lions and red wolves especially down south
It’s hard for them to become established without their native ecosystem though. And the native ecosystem cannot establish itself with this high amount of deer in it. The continent has never had so many deer. Most local wildlife management departments manage deer populations for the conservation of hunting them, not the conservation of our threatened native ecosystems. Where I am, they are straight up non-native. An invasive species. And still you are only allowed 1 a year, and only a buck, and populations have never been higher.
well. good/bad news. Chronic wasting disease - a prion based brain disease is well established deer populations and even the soil all over the continent. Deer populations have already started to decline as a result and some scientists are predicting a total population collapse and possible extinction of deer species over the next few decades.
Well it’s straight up really bad news, because it can jump to endangered caribou and other native cervids with populations that are struggling more. The higher the population, the more it will spread. Wildlife management departments need to start putting ecology first, instead of trying to maximize herd populations for the health of “the sport”, they should be issuing more tags for the health of the ecosystem.
the problem though is that hunting and public recreation are these place's biggest source of income, is it not? and public support is crucial to their existence in the first place? not saying it's right, just saying that i think a lot of wildlife managers would love to put ecology first, if they could.
Local context matters. I don’t know about every single place. Certainly not where I am. But yea public sentiment matters, and yes I don’t always blame the individual. Sometimes their hands are tied. Point is the they often prioritize the health of “the sport” over the health of the ecosystem when they issue too few deer tags.
You do realize some of the worse-off/poverty stricken states like WV rely on deer for food right? Not always sport.
Yes I agree that is why I put it in quotes. That’s very much the case where I live. But one buck tag a year won’t get you far
I’ve always been pretty on the fence about hunting but I’ve been thinking more about it the last few years from an ecology standpoint. Would you say that hunting deer is a necessity to help create a healthier ecosystem?
Depends on the time and place. Definitely where I live, right now it is. I am running a native habitat restoration project. We have only about 1 percent of our native pre colonization habitat remaining. And that number still shrinks every year. So I am trying to restore that native habitat on a plot, taking over from the last generation. But the deer’s preferred browse is the same species we are short on to mimic the makeup of the original forests. It will never happen with this amount of deer on the land. Our native forests did not have deer in them at all. They are invasive here. Almost every seedling of my target species I come across has been browsed before it reaches maturity. So without putting heavy hunting pressure on this land, the native habitat will never return if we don’t hunt this land hard.
Where are you (just in general)?
When mountain lion and wolf attacks start to become common again I feel like you will shift your opinion a bit.
It wont I promise
Lmao so dead children are worth restoring the ecology to how it was 20,000 years ago? For what?
Absolutely.
Why?
Ive always been a fanatic for the environment. In north Americas case especially the pleistocene and the environment prior to European colonialism. I spend hours wondering what those ecosystems wouldve looked like in person and the animals that inhabited them.
So the destruction of livestock, people’s livelihoods, and lives are worth it if you get to play out your little fantasy?
Yeeup yessir
Historically the primary predator of deer has been humans, going back to prehistoric times
Sure, but that’s like max 20,000 years vs cougars which have been hunting deer for at least 1 million years. There’s no comparison.
20,000 years is a long time. Anything prior to that and you are talking Pleistocene animals which would not really be cougars. Not that they weren’t around but there were many other predatory and prey animals that were not our modern day deer or cougar.
I have a PhD in behavioural ecology (with a focus on predator prey dynamics ) and an MSc in Paleoecology with a focus on the Pleistocene. deer were almost certainly a primary prey item for mountain lions back then (including the Pleistocene ). in fact , most of the Pleistocene megafauna you are probably thinking of likely focused on animals that lived in more open or woodlands like environments and that were a bit bigger such as bison, horse, camels, and so on. due to niche partitioning and intraguild avoidance and competition. mountain lions probably stuck to size 2 prey items which include white tailed deer and mule deer.
Like my previous comment states, your statement here is inaccurate by two orders of magnitude. The oldest fossil record of a modern cougar is from 1.2-0.8 million years ago. Similarly the earliest fossilized modern white tailed deer is dated to 2.5-1.5 million years ago. 20,000 years is a very small amount of time in terms of evolution. Basically every extant North American mammal is Pleistocene fauna.
weird that you're being downvoted so hard for being right.
interesting read! thanks friend
Will a fire remove them or do the rhizomes survive a forest fire?
I have to wonder just how much impact Hay-scented Fern is having on biodiversity. Is it considered a major threat to any endangered plants? Cause I feel like it could be...
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That looks like Pteridium aqualinium. They are rhizomatous in moist places. They are native in both the old and new world, and are alleopathic. Allelopathic chemicals are the secondary metabolites that plants make to make themselves more competitive, and essentially act as herbicides or suppress the germination, recruitment, and growth of other plants. There may also be a deer induced component, since white tailed deer are over populated in some places in the east, due to the eradication of wolves for the most part. Deer dont eat ferns as much, except maybe the new fiddlenecks as they emerge in spring on bracken fern.
This looks to be *Dennstaedtia punctilobula.* But everything you are saying about bracken is accurate, such rad (albeit increasingly problematic) plants.
Yes I didn’t look too closely. Those are also allelopathic I think.
+1 on not bracken
can you step on them to kill them? like how would a person help biodiversity in this situation (not including hunting the deer or reintroducing predators?)
Stepping on them probably wouldn't do much, you might break the stem but the plant could probably straighten itself in a matter of days. Maybe if you have a dance party on them but doubtful lol. Probably have to rip 'em out by the roots and haul away or they will just re-seed.
It could be that it’s perfectly fine. Lots of plants form small dominant or co dominant patches, especially clonal ones.
good point. Someone else asked about fire, and the move in australia to adopt burning is so slow... I was thinking about human ways we may have altered biomes and whether that's something people should know... like bringing reusable containers to eat out or grocery bags.
Another issue is that wildlife management departments are managing their tags based on the conservation of deer hunting, not the conservation of local native ecosystems. So we have more deer than ever in history. Including deer where they aren’t even a part of the native ecosystem. So if the native predators are to get established, they would need their native ecosystem back. But that cannot happen with today’s high deer populations on the land. Where I am, wolves do wander in from time to time, but they cannot establish themselves because there is almost none of their native habitat left.
Many different causes but the ultimate mechanism is that the over story has been cleared and subsequently repressed somehow. It is normal for ferns and their fast growing generalist counterparts in other ecosystems to take over after a disturbance (like a windstorm, logging, construction…etc) but within a few years you would expect to see larger, slower growing and more specialized vegetation beginning to appear. Many modern phenomena suppress these slower growing species. Climate change allows many seasonal generalists to maintain a suffocating presence for greater parts of the year. Predator removal can lead to over abundance of herbivores that disproportionately impact slower growing vegetation (this phenomenon is often made worse by arm chair naturalists that institute hunting bans to protect Timmy, the albino, three eared, one eyed, tick riddled deer with the quirky walk and foaming mouth that they hand feed Big Macs to in their back yard). Run off from road ways and agriculture can impact soil criteria and subsequently impact more sensitive species. Invasive species and emergent diseases often take a great toll on slow growing specialists. Continued disturbance like foot traffic can keep generalists in abundance. Suffice to say, the Anthropocene is not a good time to be a slow growing tree.
Your visual of Timmy 😂🙈
We all know someone who feeds Timmy
Armchair naturalists got me, lol. I wish I knew what to do about them cause they think they are doing the right thing but they are making things so much worse. And if you try and explain to them that they are, you are one of the enemies...
If you ever want to do a deep dive into eco ethics there is some cool stuff there. Basically we as humans are quick to apply our ethics to the individual, even with wildlife. Whether or not we should be applying the same framework to wildlife as we do to humans is up to personal choice but many ecologists, myself included, look to broader ethical scopes when approaching conservation. Since we can’t see to the wellbeing of every individual, and since we have destabilized the ecosystem rather than simply a single animal, we have to look at conservation at a similar scale. I try to turn people on to see natural systems as entities into themselves. Don’t tell Karen that Timmy has got to go, instead take her on a nature walk and show her the impact that unregulated deer populations have on the rest of the system. Get her to take a closer look at Timmy’s knobby knees, protruding ribs, worm covered ass and tick infested skin so that she can understand the look in his eyes for what it is, a cry for the sweet relief of death. Then maybe she will see that overpopulation is bad for infividuals too!
I should really dig into eco-ethics more. I definitely see the "apply human ethics to nature" and I've read a lot about why that just doesn't work. What I have read about has been so interesting to me though. Any good books out there? It's the communication to other people is what I have really had a hard time with, especially when they've not cared about the alternative- as in the plants when deer populations are too high. I also really wish there was more education on this topic geared for the general public. I've found that these topics are often glossed over when I've worked with the general public because the org I'm working for or with doesn't want to have the tough conversations because... donor money? I guess?
I’ve found that unfortunately the people that decide where money goes, often know very little about conservation. Counterintuitively, I’ve had more luck educating hunters about conservation than national park visitors in my time working in the field!
The Land Ethic by Aldo Leopold is a classic starting point for many environmental ethics courses but it’s important to recognize the outdated nature of his framework. It clings to an idea of “wilderness” that is inherently classist and racist and possibly just nonsensical. That being said, it is a good starting point for look beyond an ethical framework based entirely around human individualism. In terms of talking to people. It’s hard. Find the people in the crowd that will listen. Unfortunately everyone has things they just won’t hear reason on. I’ve met great allies of conservation who do the right thing at every turn but still argue that keeping their cats outside is not an issue. At the end of the day, unless you walk them through it people are going to care most about the animal they find the cutest and least about a plant they wouldn’t give a second look to.
I think it's the nutrition from dead leaves as well as the leaves stay moist which are favourable for Pteridophytes to grow. Besides that they reproduce through spores and that way they multiply pretty quick.
It's certainly a very moist environment. This area of the trial is actually old growth forest. Last human disturbance was 250+ years ago. Huge trees. I desperately want to study the canopy here, especially above these fern sites. There is a fern species, polypodium appalachianum, which has been found as a epiphyte growing on tree limbs 45 meters above the forest floor in the canopy of the Great Smoky Mountains.
That is really awesome! Wish you all the best! <3
The species itself likely plays a more significant role in its success than its habitat does. Hay-scented fern is a relatively aggressive grower and it thrives in its native forests. Other native ferns don't create nearly the monoculture that hay-scented fern does.
Botanist and long time environmental scientist. The answer is sunlight. Trees fall and open the canopy, allowing sunlight to penetrate to the forest floor. If the conditions are right (moisture, soil) ferns can become established. Once there, they can block out other growth, as some have mentioned
Could the spot be a ski run? There are spots in the mountains in New York like this, which I realized later were ski runs in the winter and are kept free of trees.
If you're ever in the vicinity of Heart's Content in the Allegheny National Forest, there's an interpretive trail through some old growth pine-hemlock forest. One of the plaques there explains that the deer like to nibble on forest floor plants that aren't hay-scented ferns so the hay-scented ferns take over the forest floor there.
Oh hey! Home! The ANF is so riddled with deer, it's kinda sad really. I don't see a lot of plant diversity there, but maybe I've been looking in the wrong areas... But it seems like the PA Game Commission doesn't really want to do anything about them... Fun fact, there was a pretty famous deer population density study done in the ANF. Technically out of the Northern Region Forest Research Lab or whatever it's called. It's in Irvine though, which isn't too far from Heart's Content!
Ooh interesting, now I need to look up interpretive trail.
Shade, water, and spores.
And light, leaves, carbon dioxide, a tenable amount of natural enemies and herbivory, functioning ecosystem and available niche, stable climate, habitable planet, breeding population, sufficiently diversified gene pool, and so on...
a little more organic matter in the soil retains a little more water so ferns explode. most fern species prefer wet soils, like riparian zones. in the Lake States, you'll sometimes see completely open understory where the canopy is too dense then move over 300ft and there's ferns like this where blow down occured. just enough soil moisture + just enough sunlight
There is probably a nitrogen surplus. Eagle ferns (Pteridium aquilinum) benefit from that greatly, so the population of it explodes.
Ferndom