That's a Eastern Cottonwood (Populus deltoides)

Click the link below for a great discussion on it, including why it's my most favorite tree.

Here is a link that might be useful: Eastern Cottonwood

Think I lost a bet then. AND this is a very common large tree in my area. We've had a very wet spring and then this first good high wind storm after the leaves finally opened toppled quite a few trees by the roots.

Am I correct in thinking the leaf edges are more serated(sp) than typical for cottonwood? I'm not much good at identifying trees that aren't in my yard.

Here is a link that might be useful: Uconn Cottonwood

Doesn't look typical of Populus deltoides, not least from the large leaf serrations Toronado mentions; I'd suspect it may be one of the many hybrid poplars that have been bred for timber production.

Resin

No, I completely disagree with Resin (pineresin).
The leaves (including the bark) in your pictures are 100% definitely typical of Eastern Cottonwood (Populus deltoides) I've looked at them for many years.

The leaf pictures in the link you posted toronado3800 (Uconn Cottonwood) could possibly be a misidentified hybrid cottonwood such as (Populus deltoides x Populus nigra) or are very young immature leaves which usually have very small teeth.
A mature Eastern Cottonwood usually has larger teeth exactly like your pictures, but how big and the number of teeth vary with the age of the cottonwood, slight genetic variations, and amount of light the leaf gets (less light= larger and smaller/more teeth). And the age of the cottonwood (young cottonwood tree=large leaf with tiny teeth) Mature cottonwood trees in bright light=smaller leaves with larger and less teeth. Also leaf shape can vary, some have more rounded heart shaped leaves, and some are very triangular with a long tip.

I know for sure that the cottonwood in your pictures is 100% Eastern Cottonwood (Populus deltoides) by the looks of it. And what reinforces Eastern Cottonwood even more is its location, it's located by lakes in a old forest at Spanish Lake Park, just 1 or 2 miles from the Mississippi river.

Take a look at these Eastern Cottonwood pictures below.
Here are some more links and info:
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Eastern Cottonwood Pictures
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Eastern Cottonwood Pictures
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National Champion Eastern cottonwood picture
Oldest Eastern Cottonwood in the U.S. (309 years old)

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A little info I read from the book "Natural History of the Chicago Region" by Joel Greenberg.
This is a Eastern Cottonwood that was called the Potawatomi Tree, located near Chicago, IL. It was cut down in 1903 due to safely concerns. It was about 130 feet tall, 95 foot branch spread, and a girth of 41 feet. It was said that 30 people could fit inside it. It was thought to be 500 to 600 years old, but I think it was likely 400 to 500 years old. So it would have sprouted around 1430. People once said that a bear made it home for a while.
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This male Eastern Cottonwood near us is about 100 ft tall with a spread of 80 or 90 ft, and a trunk circumference of 200 inches. I've now got a rooted and growing clone of this huge old cottonwood tree in a pot. They are pretty neat how easy the twigs root in early spring.

a good reason not to plant one close to the house.. eh???

i have seen a few giants like the prior post .... on the rivers edge ... in the flood plain ....got to think they really like a lot of water ..

lol ...ken

Yep, a good reason not to plant one near a house. And definitely not a tree for most people that like a spotless very neat yards, but for me they are a great, very beautiful, super fast growing tree for bare sites with no trees, if given enough space away from house, cars, septic systems etc.

I tend to like the big cottonwoods in the parks and farm fields around here. And yeah, the must LOVE the water and not mind being flooded occasionally. Soo many are huge. There's a gnarly huge one by the ferry landing at Kinder's Resturant that looks like barges used to tie off and run into it.

The monsters just aren't usually the right choice for quarter acre lots under power lines so they get bad reps.

The park service here has returned my emails in the past. I'll send them a link or the pics and see if I get a reply about the tree id. should know since they've no doubt had to cut it up so kids could play on the swing set near by lol