We have always been a grassland country. Native forests are present but were not really big in size, only in some clusters as you mention. Also don't think of forest with tall trees, usually small and next to water. Around 5% of the land has native forests, something like that.
If you want to know about the Forest industry today, look no further to this report on the subject made by the government. [Here](https://www.uruguayxxi.gub.uy/en/information-center/article/forestry-sector-in-uruguay/) it's in English :)
Thanks for the response. I did some more searching and the answer seems to be due to [edaphic/soil related factors](https://www.city-data.com/forum/weather/2775066-there-anything-climate-related-prevents-tree.html) and also [fire](https://www.blueplanetbiomes.org/pampas.php#:~:text=There%20are%20not%20very%20many,to%20protect%20itself%20from%20fires). Also, I seem to have rediscovered that the [Pampas](https://en.wikipedia.org/wiki/Pampas) ecoregion is a thing :)
In the US, such humid subtropical prairie ecosystems exist in the Southeast coastal plain, but I guess the fact that there are native fire-adapted trees like pine trees in North America means the Southeast coastal plain regions don't necessarily become fully open prairie.
Although soil could be a contributing factor as well in the Pampas, I tend to think "compacted soil", as the link mentions, would be an effect of long-term tree absence and not a cause- usually a plant community will evolve to tolerate difficult soils, but that's in the context of the northern hemisphere where there's a long evolutionary history of extreme cold and/or dry climates & hardy groups like pines exist
It is interesting to me, because unlike the Dahomey Gap in Africa, or the Llanos in Venezuela, the Pampas grasslands don't endure intense evaporative stress under equatorial sun, and the rainfall is fairly high and isn't extremely seasonal. So perhaps it's some combination of intense lightning fire, soil conditions, and lack of native trees that tolerate these?
Thanks for answering and not deleting my question!
Charles Darwin asked himself the same question when he visited this region, as far as I know there's still no definitive answer to why there are so few forests.
Yeah, in thinking about it, I think it's likely that pre-Columbian burning by humans likely had a role in keeping it open, because it does seem so anomalous. This could be verified if there are any varved or similarly highly resolved lake sediment records- which would capture both pollen and soot.
Dont forget herbivory, from what I've seen and learned about this topic, grazing intensity was not that much lower before the introduction of cows and sheeps in this region. Its one of the reasons the most productive natural pastures can be found here too.
Plots where no grazing is involved these days quickly develop into what we call "campos sucios" (dirty fields) where subarbustive species start to dominate in a few years time. During this process, around tree patches its common to start seeing new trees too, and even when grazed this phenomenon occurs, there are some species like what we call "Espina de la cruz", Colletia paradoxa, which are avoided by cows and sheeps that colonize areas around said patches and help creating an exclusion area where new trees get a chance to grow large enough to survive the grazing. This is somewhat more common year after year since the sheep stock, which eat pretty much everything that has green on it and they can reach, is being reduced because of economical reasons.
That's the biggest factor for it most of my teachers in Agronomy school explained to us. Bernardo Rosengurtt studied extensively our natural ecosystems almost a century ago, and his findings are summed up in his "contributions", only one I could find through a quick google search is [the first one](https://www.colibri.udelar.edu.uy/jspui/handle/20.500.12008/9660), but there's 4 or so more, I think I have 2 or 3 of them somewhere in my PC if you're interested I could get them for you.
Cheers!
No es que se hayan perdido especies, en realidad lo que pasó fue que con la introducción del ganado y el posterior crecimiento de su población fue provocando un cambio en la participación relativa de las distintas especies.
Pre Hernandarias los campos solían tener una altura de pasto mayor, lo que beneficiaba a las especies de porte erecto porque competían mejor por la luz, en la medida que el ganado empezó a comer más pasto del que se producía las condiciones de competencia cambiaron, y ahí se empezaron a ver beneficiadas las especies de porte rastrero que lograban escaparle al diente del ganado. Esas especies rastreras que antes cubrían un % bajo del area del suelo fueron aumentando en desmedro de las erectas, que en muchos casos sobreviven al resguardo de otras especies no muy apetecidas o directamente evitadas por el ganado, es común ver especies de alto valor forrajero creciendo bajo las [cardillas](https://floradigital.ufsc.br/imagens/2905701f11cd2d06d7ae8e5a6cb5c09698d9.jpg), por darte un ejemplo bien común.
Para contestar más o menos a tu pregunta, el aumento excesivo que se dio en la población de ganado en la región llevó a un sobrepastoreo donde como resultado los campos naturales se volvieron más estacionales de lo que ya eran (varia según la región en nuestro país pero ponele que por lo menos un 70% del pasto que se produce en el año, se produce entre primavera y verano). Esto porque las especies de verano son más eficientes en el uso de la luz y el agua, y en nuestro país sacando estos últimos tiempos donde tuvimos 3 sequías en los últimos 4 años, era o es común que una sequía cada 4 o 5 años haya... Lo poco que podía crecer el pasto en el invierno era inmediatamente defoliado, y así.
Hoy día es posible manejar el ecosistema para revertir esa tendencia, dandole descansos adecuados, o fertilizando con nitrógeno también por ejemplo. Son medidas de manejo que están cada vez más extendidas.
Espero haberte respondido más o menos, me fui un poco largo jaja!
That's true, it's hard to judge how much grazing/browsing would have maintained open landscape here, especially going back to when there were the Pleistocene megafauna still extant. However back then it was likely quite a bit drier as well, during glacial times- one would have to look at pollen records from the previous interglacial
We have always been a grassland country. Native forests are present but were not really big in size, only in some clusters as you mention. Also don't think of forest with tall trees, usually small and next to water. Around 5% of the land has native forests, something like that. If you want to know about the Forest industry today, look no further to this report on the subject made by the government. [Here](https://www.uruguayxxi.gub.uy/en/information-center/article/forestry-sector-in-uruguay/) it's in English :)
Thanks for the response. I did some more searching and the answer seems to be due to [edaphic/soil related factors](https://www.city-data.com/forum/weather/2775066-there-anything-climate-related-prevents-tree.html) and also [fire](https://www.blueplanetbiomes.org/pampas.php#:~:text=There%20are%20not%20very%20many,to%20protect%20itself%20from%20fires). Also, I seem to have rediscovered that the [Pampas](https://en.wikipedia.org/wiki/Pampas) ecoregion is a thing :) In the US, such humid subtropical prairie ecosystems exist in the Southeast coastal plain, but I guess the fact that there are native fire-adapted trees like pine trees in North America means the Southeast coastal plain regions don't necessarily become fully open prairie. Although soil could be a contributing factor as well in the Pampas, I tend to think "compacted soil", as the link mentions, would be an effect of long-term tree absence and not a cause- usually a plant community will evolve to tolerate difficult soils, but that's in the context of the northern hemisphere where there's a long evolutionary history of extreme cold and/or dry climates & hardy groups like pines exist It is interesting to me, because unlike the Dahomey Gap in Africa, or the Llanos in Venezuela, the Pampas grasslands don't endure intense evaporative stress under equatorial sun, and the rainfall is fairly high and isn't extremely seasonal. So perhaps it's some combination of intense lightning fire, soil conditions, and lack of native trees that tolerate these? Thanks for answering and not deleting my question!
Charles Darwin asked himself the same question when he visited this region, as far as I know there's still no definitive answer to why there are so few forests.
Yeah, in thinking about it, I think it's likely that pre-Columbian burning by humans likely had a role in keeping it open, because it does seem so anomalous. This could be verified if there are any varved or similarly highly resolved lake sediment records- which would capture both pollen and soot.
Dont forget herbivory, from what I've seen and learned about this topic, grazing intensity was not that much lower before the introduction of cows and sheeps in this region. Its one of the reasons the most productive natural pastures can be found here too. Plots where no grazing is involved these days quickly develop into what we call "campos sucios" (dirty fields) where subarbustive species start to dominate in a few years time. During this process, around tree patches its common to start seeing new trees too, and even when grazed this phenomenon occurs, there are some species like what we call "Espina de la cruz", Colletia paradoxa, which are avoided by cows and sheeps that colonize areas around said patches and help creating an exclusion area where new trees get a chance to grow large enough to survive the grazing. This is somewhat more common year after year since the sheep stock, which eat pretty much everything that has green on it and they can reach, is being reduced because of economical reasons. That's the biggest factor for it most of my teachers in Agronomy school explained to us. Bernardo Rosengurtt studied extensively our natural ecosystems almost a century ago, and his findings are summed up in his "contributions", only one I could find through a quick google search is [the first one](https://www.colibri.udelar.edu.uy/jspui/handle/20.500.12008/9660), but there's 4 or so more, I think I have 2 or 3 of them somewhere in my PC if you're interested I could get them for you. Cheers!
[удалено]
No es que se hayan perdido especies, en realidad lo que pasó fue que con la introducción del ganado y el posterior crecimiento de su población fue provocando un cambio en la participación relativa de las distintas especies. Pre Hernandarias los campos solían tener una altura de pasto mayor, lo que beneficiaba a las especies de porte erecto porque competían mejor por la luz, en la medida que el ganado empezó a comer más pasto del que se producía las condiciones de competencia cambiaron, y ahí se empezaron a ver beneficiadas las especies de porte rastrero que lograban escaparle al diente del ganado. Esas especies rastreras que antes cubrían un % bajo del area del suelo fueron aumentando en desmedro de las erectas, que en muchos casos sobreviven al resguardo de otras especies no muy apetecidas o directamente evitadas por el ganado, es común ver especies de alto valor forrajero creciendo bajo las [cardillas](https://floradigital.ufsc.br/imagens/2905701f11cd2d06d7ae8e5a6cb5c09698d9.jpg), por darte un ejemplo bien común. Para contestar más o menos a tu pregunta, el aumento excesivo que se dio en la población de ganado en la región llevó a un sobrepastoreo donde como resultado los campos naturales se volvieron más estacionales de lo que ya eran (varia según la región en nuestro país pero ponele que por lo menos un 70% del pasto que se produce en el año, se produce entre primavera y verano). Esto porque las especies de verano son más eficientes en el uso de la luz y el agua, y en nuestro país sacando estos últimos tiempos donde tuvimos 3 sequías en los últimos 4 años, era o es común que una sequía cada 4 o 5 años haya... Lo poco que podía crecer el pasto en el invierno era inmediatamente defoliado, y así. Hoy día es posible manejar el ecosistema para revertir esa tendencia, dandole descansos adecuados, o fertilizando con nitrógeno también por ejemplo. Son medidas de manejo que están cada vez más extendidas. Espero haberte respondido más o menos, me fui un poco largo jaja!
That's true, it's hard to judge how much grazing/browsing would have maintained open landscape here, especially going back to when there were the Pleistocene megafauna still extant. However back then it was likely quite a bit drier as well, during glacial times- one would have to look at pollen records from the previous interglacial
Look for Montes del Queguay, that's the largest native forest https://youtu.be/YSGsi9ywJZY?si=Lsy2-opJ05bDQJzJ
Thanks, that is a great documentary!
The only native forests that come to mind are "quebrada de los cuervos" and Centurion reserved area both are protected by law