Female Gypsy Moth Laying Eggs

A couple of weeks ago I spotted a moth on a tree in the yard.  It took me a couple of seconds to  realize it was a female gypsy moth.

That  gypsy moth was in the middle of laying its eggs.  I could have destroyed it right there and then but decided against it.  I thought  maybe a few readers of this blog might want to see what an egg-laying  gypsy moth looks like.

The brown egg mass it deposited contains hundreds of eggs, most of which will survive the winter and hatch out next spring.  Cold winter weather doesn’t bother them at all. After the caterpillars  hatch from their eggs, they will climb the tree and start devouring leaves.

This female gypsy moth is laying an egg mass that contains hundreds of eggs.

The next time you’re outside enjoying your yard, it might not be a bad idea to look at your trees for signs of gypsy moth egg masses. They normally lay eggs on the trunk of a tree or on lower branches. You can also find them on backyard swing-sets, picnic tables, RVs — just about anything that’s left out side.

It’s a good idea to destroy these eggs masses as soon as you find them.  Scrape them off of the tree and throw them in the trash.  Don’t let them lay on the ground thinking that you took care of them. They’re pretty tough and will hatch even if left on the ground all winter.

Now I have a bit of a dilemma, do I take off that egg mass from my tree? Or do I leave it there until spring and take pictures of hatching caterpillars for this blog?

Bob

A Dogwood Makes Its Home

We have a wild area on our property that we keep for birds . It’s about an acre in size and is home to a wide variety of wildlife.

This spring, for the first time, we noticed a wonderful dogwood tree hidden in a rarely visited corner tucked in on the south side of  a pine tree. It is in full bloom and rivals anything you might find in a landscape nursery.

Our wild dogwood is about 18 feet tall.

It really is a stunning sight.

The tree is covered with large white blossoms.

We never would have had this surprise if I was sprucing-up this wild area every year with my brush cutter and weed-whacker. I probably would have cut it down long ago without even realizing what it was.

Sometimes, it pays not to organize the wilderness.

Bob

Conservation District Tree Sale Seedlings

The trees I ordered from the Monroe Conservation District arrived Friday. I drove over to pick them up first thing in the morning and got there shortly after they opened the doors.

My package  contained 50 trees — 25 white pine  and 25 white cedar– so it was small enough to carry in one hand. The tree seedlings look beautiful.

I placed my seedlings in a bucket of water for a while to re-hydrate them a bit before planting.

White pine grows very fast in our sandy, somewhat acid soil. I have never planted white cedar here but I’m sure that they will do well too.

Fifty seedlings doesn’t take too long to plant. I noticed other folks picking up orders that were much larger than mine. Some had several gunny sacks worth of seedlings. I mentioned to one fellow walking out with a large order that it looked like he had a big project on his hands — he just grunted and walked out to his truck with the last of his order.

Judy and I planted our  seedlings Saturday morning. The cool weather this week will help them get off to a great start.

Bob

 

 

 

Overwintering Potted Trees

The gardens outside are buttoned up for winter.  I took advantage of the cold temperatures a couple of weeks ago to heel in the last of the plants I wanted to save over winter. Usually I like to get this job done by the first week of December.

The only plants left were some of the potted trees that I’m saving for some bonsai and other projects.  In addition to my 15 years old bonsai, I tucked away a fewAlbertaspruce, some maples, a couple of tamarack and a small assortment of other potted trees.

There’s a nice sheltered area in our yard under some pine trees where the plants spend the winter.

I start out preparing an overwintering spot by digging a shallow hole that is about half the diameter of the pot. The pot goes into the hole sideways so that the plant is lying right on the ground.  I take the soil dug from the hole and cover the pot.

Next, I cover the buried pot and the top of the plant with mulch.  Usually I can rake up enough pine needles to do the job.  This year I decided to use wheat straw because of the number of plants I had.

Some old garden fence keeps the straw mulch from blowing away.

My success rate has been quite high using this method.  Placing the pot on its side keeps out excess water that may freeze and damage the pot. Laying the trees on the ground protects the branches from extreme temperatures.  The mulch protects the plants from exposure to the winter sun, which can dry out small branches.  Moreover, it serves as blanket to protect the plants in case we don’t get snow cover.

The soil hasn’t frozen yet and the plants haven’t been exposed to really cold temperatures so there is still time to get those valuable plants tucked in for winter.

This year it looks like I could have waited until the first week of January. I wouldn’t want to bet on it happening again next year.

Bob

 

 

Fall Webworms

Fall webworms are back.  They are really becoming more apparent as they grow and their webs get larger.

Fall webworms nests start to become apparent in late summer.

This is not the same caterpillar we saw in the spring; those were the Eastern Tent caterpillar.

Because fall webworms emerge in late summer, they don’t have a chance to do much damage to trees but their webs sure are ugly.

Fall webworms feed on a wide variety of trees. In our area this summer, I’ve been seeing them on walnuts, oaks, mulberries, cherries and other trees.

There are a couple of options available for controlling these pests.  The simplest method is to manually pull the webs down and destroy them.  For those you can’t reach, use a chemical pesticide sprayed up onto the web.  You don’t need much because they are easily killed by most chemical insecticides.

Some people recommend spraying the biological insecticide Bt. Bt works best when the worm are small.

Try to resist the urge to burn the webs in place on the tree.  You’ll end up scorching twig bark causing more damage to the tree than the webworms.

Paper wasps are a natural enemy of the fall webworm. If a paper wasp nest is located in a place on your property where they aren’t disturbing anyone, think about leaving them there to help control the webworms.

Bob

 

 

Catalpa Trees in Bloom

Those trees covered with white flowers we have been seeing are Catalpa trees.  To me, a well-formed, fully grown Catalpa is an impressive sight.

A mature Catalpa tree blooming in rural Monroe County.

 

Catalpas have other positive attributes other than their flowers.  They grow fast compared to many other trees and can reach a height of 50 feet.   Catalpas tolerate the stressful growing conditions of a city environment, which is why so many were planted in urban areas.

In years past, farmers planted Catalpas to use for fence posts because the wood is resistant to rotting when in contact with the soil.  Nowadays, like everyone else, farmers buy their fence posts.

After flowering, long, slim cigar-shaped seedpods will form where the flowers once were giving the tree its nickname “Cigar Tree”.  These pods hang on all winter.

Not everyone likes Catalpa trees.  The branches are brittle and can break off during storms.   Some people feel its shape and large leaves give it a coarse, unrefined look.  I have to agree that a Catalpa struggling to survive in a difficult spot can look pretty ragged.   In addition, the flowers and seedpods make a mess in the yard after they fall off

Catalpa worms, the caterpillar stage of a sphinx moth, are sometimes found eating catalpa leaves.   Anglers use these worms for fish bait; fish love catalpa worms.

I remember when I was a youngster some Umbrella trees in my Grandmother’s garden.  There was a row of them, about eight feet high with a tuft of leaves growing out of the top.  Those trees were catalpas grafted with a bud from a dwarf form of the tree.   Every spring she would cut back the last season’s growth forcing the tree to form a new umbrella.   It made quite an impression on me.  The Umbrella tree form is still available at nurseries.

Catalpas are such a versatile tree, no wonder they have been so popular for so long.

Bob

 

 

 

 

 

Over-Wintered Orange Trees

We brought out our two Valencia orange trees during the warm spell we had earlier in the week.  I figured the really cold weather was behind us for the most part.  These trees are about 5 feet tall and are in 18 inch terra-cotta pots.

The two trees are part of an informal experiment I have been conducting over the past two years.  They were not kept in a greenhouse or even in the house in front of a south window; instead I put them into our semi-heated garage.  They each received some sunlight from a small south window; the size of window you would expect to find in a garage.

The temperature ranged from the upper 30’s F to lower 40’s F through most of the winter.  There were a few days when the heat was raised a bit up into the 50 degree F range.

I cut way back on watering.  They received water only five or six times during the whole winter.  I let the leaves start to wilt before I even thought about watering.  Then I watered just enough so the water began to drain out of the bottom of the pots.  Neither pot had a saucer under it so they didn’t stand in water.  They didn’t get any fertilizer either.

About mid-winter, the trees looked like they went into a kind of semi-dormant state.

Even though the trees seemed to be hibernating, the oranges that were on the tree last fall turned orange and ripened.  The fruit  didn’t get much bigger which is no surprise considering the lack of water.

There are quite a few oranges on our over-wintered orange trees.

Last night it got down to 33 degrees F and I left the oranges outside.  They looked perfectly fine this morning; they are used to the cool temperatures.

This is a good way to keep trees like these over winter if you are short on space in your house.  You don’t have room in the garage either? … well I can’t help you there.

Bob

March Is Pruning Time

The month of March is pruning time for most trees and shrubs. These woody plants have been dormant all winter. As the temperatures begin to warm up and the days get longer the plants begin to wake up. Pruning just before they break dormancy is best.

There are some exceptions to pruning in March. Spring flowering trees and shrubs are not normally pruned at this time because they formed their flower buds last year and are ready to open soon. Pruning those bushes now would mean you would  be cutting off all of those flower buds. Forsythia is probably the best known example of a spring flowering shrub.

We don’t normally prune maple trees this time of the year either. This is the time of year when the sap is running in maple trees. Pruning has the same effect as tapping a tree; it causes the sap to flow out from the wound. Although the maple is not hurt or weaken by pruning, all of that sap running out of the pruning cut can leave an unsightly stain on the bark.

Peach trees are pruned a little bit later in the spring after the weather warms up. May is better for peaches because they are actively growing and can heal quicker reducing the time the wound is open to infection.

Whenever you decide to prune keep in mind to make a proper cut. Never leave a stub of a branch after cutting. Cut back close to the limb from which you removed the smaller branch.

Always make your cut close to the limb. Don't cut so close that you cut into the limb itself.

Leaving a stub makes it extremely difficult for the tree to heal itself. Often the stub will die back and rot in place on the tree. This will leave an open area for fungus to become established and cause deeper wood to decay.

Warmer days are just around the corner. I plan on getting out and getting some pruning done this week.

Bob

New Threat to Walnut Trees

Another potential disease problem is over the horizon threatening our local trees.  This time it is the Black Walnuts that are at risk.

A fungal infection called Thousand Cankers has been killing Black Walnut trees in the western part of the United States for several years.  It has been confined to nine states in the Rocky Mountain area and westward until July of this year. Its range seemed to be associated with a different walnut called the Arizona Walnut.  Black Walnut is not native to that particular area but was brought in and planted by arborists, landscapers and others.

This summer it was confirmed that the disease had spread to at least one location in the Eastern USA,  Knoxville Tennessee.  Scientists now believe that it may have been present there for a number of years without anyone knowing about it.

At this time Thousand Canker disease is NOT present in Michigan.

The disease is caused by a fungus which is carried by a very tiny beetle called The Walnut Twig Beetle.  Despite its name the Twig Beetle  attacks larger branches or even the trunk of Black Walnut Trees by tunneling under the bark. They leave small “galleries” or tunnels in the wood caused by the beetle larvae feeding there.

When the larvae mature into adults they emerge from the branches out of small holes chewed through the bark. The fungus then infects the damaged area and causes a small lesion or “canker”.  These cankers spread very fast and merge together eventually moving from the outer bark into the cambium layer.  Each branch has a tremendous number of cankers which is how the disease got its name.

The cankers themselves are often difficult to see and identify.  A special lab test is needed for positive identification.

There is no cure or control for either the Twig Beetle or Thousand Cankers, plant pathologists are working on that though.

In the meanwhile we can help slow down the spread of this problem by not moving firewood just like we do to prevent Emerald Ash Borer from spreading.

There is no federal quarantine on moving wood products but the State of Michigan has issued its own quarantine against shipping articles made of wood from certain western states.

The USDA Forest Service has a good publication on this problem.

As I mentioned earlier, Thousand Cankers is not present in Michigan at this time. Keep in mind that there are a lot of other things that can cause a tree to show signs of  die-back  other than this disease.

Bob

Lichens on Trees

A few days ago a gardener proclaimed to me that an expert had told her that Lichens are found only on trees that are no longer growing. I don’t know what expert might have told her that but I’m sure she misinterpreted whatever may have been said.

Lichen growing on young crab apple tree.

The study of Lichens is a huge branch of Biology in and of itself. People who take an interest in that field of study often become quite rabid about the subject. I’ve been on expeditions where the Biologist talked as if the world existed for the sake of providing a place for Lichens to grow.

Lichens are actually a combination of two organisms, a fungus and an algae. They work together as one in order to survive in places where they couldn’t otherwise. The algae provides energy through photosynthesis while the fungus provides shelter and a place for the algae to live.

They can be found covering a wide variety of objects in addition to trees including rocks, roofs, bare soil and just about any other exposed surface.

On trees Lichens are harmless. They are actually quite attractive on trees adding an extra visual element to the landscape. Many gardeners will go to extreme lengths to get Lichens established on certain features in their garden. Lichens growing on the roof, on gravestones or other unwanted places is a whole different subject that we won’t cover here.

As for the gardener who thought that Lichens can be found only on non-growing trees, all she has to do is look in her own yard to see that Lichens are quite happy on actively growing trees.

Bob