What determines where oaks grow?

[Turkey Creek]

I am not an oak tree expert, but was wondering what is the major limiting factor for where oaks occur naturally? Precip? Soil type? Winter hardiness? A combination of all those?

We only have one naturally occurring oak where I live, Burr. However, when I look at other areas I see more native oaks. We have the same temp as many of those zones, maybe a little less precip but since oaks have good tap roots I cant imagine that is a major factor.

 

[yoderjac]

I know around here, spring weather is a big factor in acorn production. Untimely storms in the spring are often blamed for acorn crop failures. So, it could be that in some areas, the spring weather in not conducive to acorn production. If spring weather precludes good acorn production consistently in some areas, I can see that would be a factor as to where they would occur naturally. Oaks seem to grow in our marginal, thin, soils that are pretty acidic. We have more kinds of oaks than I can keep track of here in VA and that is true in PA as well where I used to live.

Another consideration might be competition. As I understand it, American Chestnut used to dominate our eastern forests before the blight hit and oaks took over.

Thanks,

Jack

 

[sandbur]

TC You have named the reasons. Each oaks species has a limiting factor or two for every specific location. We are trying to force the issue when we plant tees outside of their natural range. Climate change may move the natural range a bit.

In some cases an irrigation rig will move it more!

 

[sandbur]

Oaks generally prefer acidic to slightly acidic soil. If native ph is high, burr oaks or burr oak hybrids are about all that will grow.

Add rainfall into the issue on light soils. Bur oaks will sprout and grow on my light, low pH soil if we have a wet year or two. Red oaks are a real struggle.

 

[Turkey Creek]

I guess it probably has the most to do with lower pH. What pH level do you think most oaks find suitable? We have soil around us in spots that is 5.5. Is that still too basic?

 

[chummer]

As I climb in elevation on the way to camp you can tell where the oaks stop growing. Unfortunately for me they stop about 5 miles before my place. I have planted oaks and got very little growth. Late frost does a number on them.

 

[buckdeer1]

Usually it's a good assumption that if that type of tree isn't there,theres a reason.Not so on my place I planted the first oak and now have several thousand.It is low PH sandy loam.But my sawtooths grow really well in the sandier area that I took out of cropland

 

[Bowsnbucks]

5.0 to 6.0 is common soil pH in northern Pa. and we have gobs of oaks. Avg. " hot day " summer heat is around 85 degrees - winter " cold day " in the teens with a few days of -10 to zero for the coldest. Much of winter here is now 30's as opposed to teens & twenties when I was a kid.

Late freezes will hamper acorn production. So will a bad year of gypsy moths - it weakens the oaks for 2 years or so if no subsequent gypsy infestations happen. Some years, acorns are a boom - some years they're a bust. White oaks are slow growers, red oaks are faster. Our 3 main numerous, native oaks here are white, red and chestnut oak, with some black oaks scattered around. Pin oaks are more planted for landscaping here and not found in numbers in the mountains. Soil can range from clayish loam to sandy loam.

 

[Turkey Creek]

Well historically prairie fires kept trees from growing where I live except in the wettest areas. Even the Burr oaks I mentioned are really not that common. I imagine the pioneers harvested almost every tree of usable size when they first arrived. So as buckdeer1 mentioned I am not sure somethings wont grow here its just that they have never occurred here or been allowed to reach a growth stage where they could sustain themselves after the arrival of pioneers. This oak thread just wandered into my bored mind as I am here at my in-laws in suburban North Carolina where there are at least 3 different oak species growing around their property :)

 

[Turkey Creek]

5.0 to 6.0 is common soil pH in northern Pa. and we have gobs of oaks. Avg. " hot day " summer heat is around 85 degrees - winter " cold day " in the teens with a few days of -10 to zero for the coldest. Much of winter here is now 30's as opposed to teens & twenties when I was a kid.

Late freezes will hamper acorn production. So will a bad year of gypsy moths - it weakens the oaks for 2 years or so if no subsequent gypsy infestations happen. Some years, acorns are a boom - some years they're a bust. White oaks are slow growers, red oaks are faster. Our 3 main numerous, native oaks here are white, red and chestnut oak, with some black oaks scattered around. Pin oaks are more planted for landscaping here and not found in numbers in the mountains. Soil can range from clayish loam to sandy loam.

Your growing conditions seem similar to ours other than I am sure you receive much more precipitation. Our yearly precipitation total is around 30"/ year.

 

[Native Hunter]

Oaks will grow well about anywhere around here, because most soils are on the acidic side. Where you don't find many oaks is where other faster growing and more aggressive climax canopy trees (yellow poplar, sweetgum, maple, etc) like the growing conditions even better and outcompete them. I've worked for several years establishing oaks in such a place. You have to give the oaks the advantage for the first few years but eventually when they get a big enough head start, they will dominate the forest without you doing anything.

 

[H20fwler]

Oaks are a dominate tree in the woods here also, white/red and pin oak. Our soil is loamy clay to heavy clay higher PH.
We are having trouble here in the southern part of the state with oak wilt too, I agree it seems to affect white oaks the most.

 

[Turkey Creek]

Soil varies here but mostly silt/loam. We have some areas that are sandy, some with a lot of clay.

 

[bwoods11]

I've had good luck with bur oaks on slopes near a water source.

Swamp White Oak and Hybrids seem to do well on my Barnes soil which is a loam type (good soil).

 

[Bowsnbucks]

I can tell you guys that oaks here are " sunny side " of the mountain trees. We find a much higher % of oaks on the side that gets the sun. On the north side of mountains or hills, oaks tend to be located on benches that get at least 5 hours of some sun, even though it may be dappled sunlight. We don't find many oaks here in heavy shaded locations. More birch, maple, and tulip poplar on north slopes and in the shadier areas.

I know some of you guys don't have any mountains - or even hills. But the preference by oaks for sunlight seems clear. I would never try to start an oak seedling in a shaded area.

 

[sandbur]

I can tell you guys that oaks here are " sunny side " of the mountain trees. We find a much higher % of oaks on the side that gets the sun. On the north side of mountains or hills, oaks tend to be located on benches that get at least 5 hours of some sun, even though it may be dappled sunlight. We don't find many oaks here in heavy shaded locations. More birch, maple, and tulip poplar on north slopes and in the shadier areas.

I know some of you guys don't have any mountains - or even hills. But the preference by oaks for sunlight seems clear. I would never try to start an oak seedling in a shaded area.

On my lighter soils, oaks are growing on gentle north slopes or in areas with south exposure but protection from the hot and drying southern winds. We need a few wet summers to get decent bur oak regeneration. More protected locations may get a few red/pin oak types to grow. They might be a natural hybrid. I am not sure, but lots of variation in leaf shape. pH of some of this area is 4.6. Better for bur oaks, if you get rain.
Closed canopy is great for buckthorn!

 

[Bowsnbucks]

Bur - That's the difference we get from various areas. We don't get those hot, dry southern winds like you get there.

I wish we could " push a button " and pay quick visits to each other's properties ( without airports and delays !! ). It would be a cool thing to spend a day walking around and seeing what each of us has on our ground. Some of the trees and plants you guys have there - I've never laid eyes on.

 

[pointer]

In a whole lot of places fire was the cause of oaks being a dominant canopy level tree historically. Now lack of fire has them being dominant where they once weren't (former prairies) and losing dominance in other areas as more shade tolerant species (eg. sugar maple\beech) become dominant.

 

[sandbur]

In a whole lot of places fire was the cause of oaks being a dominant canopy level tree historically. Now lack of fire has them being dominant where they once weren't (former prairies) and losing dominance in other areas as more shade tolerant species (eg. sugar maple\beech) become dominant.

In Minnesota, some of that has been attributed to the arrival of the horse. The Indian turned to buffalo hunting with horses on the plains and abandoned their fire management of areas on the eastern edge of the plains. Oak savannah became hardwood forests-where they have better soil than me!

 

[sandbur]

Bur - That's the difference we get from various areas. We don't get those hot, dry southern winds like you get there.

I wish we could " push a button " and pay quick visits to each other's properties ( without airports and delays !! ). It would be a cool thing to spend a day walking around and seeing what each of us has on our ground. Some of the trees and plants you guys have there - I've never laid eyes on.

I think those winds have lead to more bush type wild crab apple trees in my area. And those limbs also the provide protection from sunscauld. My area was prairie with fingers of woods extending out into the prairie along rivers and creeks.

If you are in the hills and better soil like Stu is, things are different. Different trees and different growth forms.

Like you said, land tours with a handful of friends are a great thing. You always learn a thing or two.