Bur Oaks

The Window is Small and Closing Quickly

The time after the ground thaws to before things green up is the time to burn prairies. Also, the time after the ground thaws and before the trees bud is the time we dig up, transplant, pot, or ball and burlap trees. The window for much of what we do this spring of 2018 is a very small one.

As of yesterday, Saturday May 5, the ground is still frozen in spots. But it's thawed enough for us to do what we need to do.

We burn the prairie plots around the farm, and the prairies we have installed for customers. The burns enhance the soil, set back the weeds, and promote growth of the native plants.

We burn the prairie plots around the farm, and the prairies we have installed for customers. The burns enhance the soil, set back the weeds, and promote growth of the native plants.

The burns should be done before the prairie plants green up, as the burn forces them to start over. Unfortunately, during all this, the trees are beginning to bud. Their budding is a function of their activity, and It is not good to disturb tree roots when they become active, as doing so can kill the tree. So disturbing the roots should be done while they are dormant. 

At the tip of this Bur Oak branch you can see the buds beginning to swell. That means this tree is active, and yet we have many of them that we need to ball and burlap, pot, or transplant. So we hustled on Friday, May 4th, to get this done, thinking that by Monday, it may be too late to dig up trees.

At the tip of this Bur Oak branch you can see the buds beginning to swell. That means this tree is active, and yet we have many of them that we need to ball and burlap, pot, or transplant. So we hustled on Friday, May 4th, to get this done, thinking that by Monday, it may be too late to dig up trees.

These crooked sticks in the ground are Bur Oaks. It's hard to grow a straight one, so we plant many of them and then go through them when they get to a certain size, separating the crooked ones from the fairly straight ones. 

These crooked sticks in the ground are Bur Oaks. It's hard to grow a straight one, so we plant many of them and then go through them when they get to a certain size, separating the crooked ones from the fairly straight ones. 

The straighter Bur Oaks get either potted for later use, or balled and burlapped, after which they can be planted at any time. Paul, an employee, is digging holes in the background where the smaller and straighter ones will be transplanted. 

The straighter Bur Oaks get either potted for later use, or balled and burlapped, after which they can be planted at any time. Paul, an employee, is digging holes in the background where the smaller and straighter ones will be transplanted. 

We use a tree spade to cut the roots of tree roots. This allows us to keep the soil on the roots or, in effect, take the soil with the tree. 

We use a tree spade to cut the roots of tree roots. This allows us to keep the soil on the roots or, in effect, take the soil with the tree. 

Here's a photo taken years ago of a balled and burlapped tree that we are about to plant in the yard of the house behind. Our tree spade, which allows us to ball and burlap, allows us to dig up the trees before they become active, and then plant them throughout the rest of the spring, summer, and fall.

Here's a photo taken years ago of a balled and burlapped tree that we are about to plant in the yard of the house behind. Our tree spade, which allows us to ball and burlap, allows us to dig up the trees before they become active, and then plant them throughout the rest of the spring, summer, and fall.

Spring in Full

With our mid-April snows, spring seemed to be put on hold. Funny what a difference a week can make. By the beginning of this week, we heard our first frogs, bird sounds were everywhere, trees and shrubs were budding. Here are a few things we found mucking about in the prairie yesterday.

Here is a Purple Coneflower poking through the duff. Chances are this one germinated last year and was covered with snow in this state. Notice the bits of Bluegrass around it that are greening up. 

Here is a Purple Coneflower poking through the duff. Chances are this one germinated last year and was covered with snow in this state. Notice the bits of Bluegrass around it that are greening up. 

Here is a Monarda plant making its way.

Here is a Monarda plant making its way.

Here's a clump of Little Bluestem we pulled up, only to see that nothing on it is turning green. It's a warm season plant and needs warmer days and nights before it will become active.

Here's a clump of Little Bluestem we pulled up, only to see that nothing on it is turning green. It's a warm season plant and needs warmer days and nights before it will become active.

The Yellow Coneflower (or Grey-Headed Coneflowers) are just beginning to germinate.

The Yellow Coneflower (or Grey-Headed Coneflowers) are just beginning to germinate.

The Red and Silver Maples are budding. This is a Freeman Maple, a cross between a Red and Silver Maple.

The Red and Silver Maples are budding. This is a Freeman Maple, a cross between a Red and Silver Maple.

Elderberry, which is a native shrub, is budding out. Notice the ice on the pond in the background. By yesterday afternoon, that ice was mostly gone. 

Elderberry, which is a native shrub, is budding out. Notice the ice on the pond in the background. By yesterday afternoon, that ice was mostly gone. 

Usually the Bur Oak buds are beginning to swell by this time. But this year, there is not much happening with this Bur Oak. 

Usually the Bur Oak buds are beginning to swell by this time. But this year, there is not much happening with this Bur Oak. 

Bur Oaks on our 80 Acres

Much of the photography in this blog is taken on our 80-acre farm here on the edge of St. Joseph, in Central Minnesota. More than half of our land was too low or too wet to come under till, which means it has some remnant native plants. One of them is the Bur Oak. Indeed, the landscape of this part of Minnesota was once defined by the Bur Oak, as well as a whole system of native grasses and wildflowers. This ecosystem, or biome, we call the Oak Savanna. 

As I said in a previous post, the Bur Oak is a slow-growing tree, with a life expectancy of 200 years. Some have been measured to live 400 years, making them the longest living plants in our area.

This Bur Oak was about my height when we built our house in 1987. That makes it at least 35 years old. 

This Bur Oak was about my height when we built our house in 1987. That makes it at least 35 years old. 

One aspect of the Oak Savanna is that the trees in it are spread out, allowing sunlight to penetrate the woodland floor. Such sunlight allows for a good many of prairie, or full-sun, plants to inhabit the a savanna. And of course the oaks will have a good many partial sun/partial shade (but not dense shade) native wildflowers under them. In many ways, a good savanna looks like a prairie with Bur Oaks in it. 

Because these trees grow slowly, their wood is more dense. So, square foot for square foot, these trees have stronger, heavier wood, which is why people like them for making things and for burning. The reason one sees "Oak Fire Wood" for sale is because an Oak log will put out more heat, and burn longer, than other lighter woods like Pine or Poplar. 

This Bur Oak is easily three feet in diameter, making it a two hundred year old tree. It has grown in a lower, wetter part of our land.

This Bur Oak is easily three feet in diameter, making it a two hundred year old tree. It has grown in a lower, wetter part of our land.

I'm guessing that there were many more oaks on our property at one time, but they were cleared to create tillable land and were used for construction. 

This cluster of Bur Oaks is unusual on our property. I assume a squirrel collected and stored acorns from the nearby Oak in the previous photo. Together they make up a nice little savanna in our wetlands. Because their acorns may have all come from the same tree, they are all of the same family, and therefore sharing similarities in structure, which I look for when I walk by them.

This cluster of Bur Oaks is unusual on our property. I assume a squirrel collected and stored acorns from the nearby Oak in the previous photo. Together they make up a nice little savanna in our wetlands. Because their acorns may have all come from the same tree, they are all of the same family, and therefore sharing similarities in structure, which I look for when I walk by them.