Giant ragweed

Earlier this week I spotted a stand of giant ragweed growing next to a parking lot. That brought back memories from long ago when I had a small farm and was growing corn and soybeans. Back then there were a lot of those types of small farms around.

I was a young guy and was excited about my first crop of field corn. It was only 40 acres worth of corn, quite small even back then. I took the first truck load to the local grain elevator. The owner took one look at it and said he would not buy my corn. He told me it was contaminated with a small amount of giant ragweed seeds. He said he had only seen them once before in his entire career — lucky me.

The problem with giant ragweed seed is that although it is shaped differently, it is about the same size and weight as a kernel of corn. The seed cleaning equipment at that time could not remove ragweed seed from corn.

Nowadays, giant ragweed is all over the place. You can spot it in fields and in ditches along the roadways and competing with farm crops like corn and soybeans. It’s become a major problem on many farms.

Not only is it a major weed on farms but in certain areas, it is also a major contributor to the amount of ragweed pollen in the air. A single plant can produce ten million pollen grains a day or about one billion during its lifetime. Compare that to a another plant which produces large amounts of pollen, the corn plant which sheds two to twenty-five  million pollen grains its entire life.

Giant ragweed is not as common as its cousin the common ragweed. Because the population of common ragweed is much higher than giant ragweed, most of the pollen in the air is of the common ragweed variety.

Ragweed buds will eventually grow into seeds.
Ragweed buds will eventually grow into seeds.

Giant ragweed is native to north america. It usually doesn’t show up in an area unless the soil has been disturbed for some reason, like tilling a field, or in this case, building a parking lot.

Fortunately, the grain dealer eventually took pity on me and bought my grain. Regulations allow a shipment of corn to contain a tiny percentage of weed seeds, not enough make a difference in the final product. So much corn was coming in during that harvest season that when my minuscule crop was mixed in to the rest, it virtually disappeared into the tons and tons of corn from other farms.

Bob

 

Different approach to controlling field bindweed

I came across an old publication about dealing with weeds in farm and garden situations. The author discussed why weeds grow where they do and how we can use that knowledge to reduce weeds naturally without the use of herbicides. Needless to say, that is a large and complex topic, too big to go into detail here.

One item that did jump out at me was a unique way of killing field bindweed.

Field bindweed is one of the most tenacious weeds we have in the garden. If you have ever had a bindweed infestation in your garden, you know what I’m talking about. It grows from a net work of underground roots that will grow several feet deep and have a lifetime of twenty years or more. I’ve blogged about this weed in the past.

Even after being cut back all season, this field bindweed still managed to push its way through mulch.
Even after being cut back all season, this field bindweed still managed to push its way through mulch.

Other than using chemical herbicides, the traditional way of controlling bindweed is to starve the root system by cutting back the tops whenever you see them. That may mean as often as every few days or so, especially early in the season. By cutting back the tops, you remove the leaves stopping all photosynthesis. That forces the plant to use stored energy as it sends up new shoots. Eventually, the plant runs out of energy and dies. That process may take a few years.

The author of the weed publication offers a different take on bindweed. He mentions, almost in passing, that dahlia roots secrete a substance that kills field bindweed. I’ve been trying to think back to all of the hundreds or even thousands of dahlias I’ve grown in the past and can’t seem to recall ever seeing bindweed growing with dahlias. I’m not growing dahlias this year and have not grown them for several years.

You would still need to control other weeds in your dahlia area.
You would still need to control other weeds in your dahlia area.

If the dahlia vs bindweed theory is true, that gives gardeners a new ally against this noxious weed. It would mean taking a piece of ground out of normal production and growing dahlias there for a season, which would not be all that bad of a thing I suppose.

Growing enough dahlias to cover a large area presents a whole new set of challenges. That is a topic for another time.

Bob

Moth mullein welcome in the garden

There’s some new unexpected members to our garden family of plants this year. It is a group of moth mullein plants.

I’m not really sure how they got there. I figure they most likely hitched a ride as seed in soil from some other plants that I transplanted from someone else’s garden a couple of years ago.

Since moth mullein is a biennial, it takes two years to bloom. The first year for all biennials is a nondescript growing stage which is why I hadn’t noticed the mulein until now. If I was a more tidy gardener, I probably would have pulled them out last year thinking they were some kind of weed seedlings.

Moth mullein is a non-native species so, many people consider them actual weeds. Originally they were brought to this continent as a decorative flower and useful herb — it has some insecticidal properties.

Moth mullein in bloom.
Moth mullein in bloom.

While it may be an immigrant to this country, moth mullein seem to have very little impact on the native ecosystems of our area. They really can’t compete with well-established native plants. However, each plant produces thousands of seeds a year and tilling the soil tends to stimulate their germination. In the garden they may eventually wear out their welcome. In some states they are classified as noxious weeds but not here.

American goldfinches feed on the tiny moth mullein seeds. I saw a pair of goldfinches checking out my plants today. The seeds are not ready yet, so they decided to leave before I could get a photo of them. The seeds are pretty small, about one millimeter long, and can sprout even after laying for a hundred years.

I’m not too worried about the mullein taking over my garden just yet. They are behaving themselves in a very dry flower bed and are only a couple of feet tall. In your garden, if it has fertile soil and is well watered, they might grow twice that size.

Moth mullein is a perfect candidate for an English cottage garden where plants are expected to reseed themselves year after year.

Seeds are available through mail order seed catalogs and online sellers. Of course you can always collect some from the wild since they are not endangered nor invasive in Michigan.

Bob

Watch out for poison ivy when collecting leaves

The fall color season is nearing its peak. It’s a beautiful time of the year to be outside watching the leaves turn a little bit each day.

Collecting those leaves is a lot of fun too whether you use them for decorating or for helping your kids make that time honored school project, a leaf collection.

Many people use leaves they’ve collected from fall color tours or from their own backyard to decorate their homes.

Once you collect leaves and bring them indoors, they’ll easily hold their vibrant colors until Thanksgiving.

Be careful though not to bring a health risk into your home.  Poison ivy could be lurking among your hand-collected decorating materials.

Poison ivy vines are often found growing up tree trunks and even on sides of buildings. In the fall, it produces one of our most brilliantly colored leaves. It’s bright-red autumn leaves are very attractive and would make wonderful indoor decorations except for one thing — they are still poisonous!

This poison ivy is just starting to turn color.
This poison ivy is just starting to turn color.

Every year I hear of someone “catching poison ivy” in the late fall even though they claim they have never been anywhere near the stuff. Many times their poor dog or cat is blamed for coming into contact with poison ivy and bringing it in on their fur when, in fact, it is the owner’s leaf decorations that are to blame.

To avoid bringing in poison ivy, learn how to identify it. The old saying “leaflets three, let it be” holds true even in the fall. Before picking up an unidentified leaf, take a few seconds to look for nearby vines climbing up trees or walls.

Virginia creeper, on the other hand, looks similar to poison ivy but it has five leaflets instead of three. Virginia creeper is harmless.

Be wary if that bright red leaf is not something you can easily identify before you add it to your table’s centerpiece.

Bob

Keep an Eye Out for Poison Ivy

Most plants made excellent growth during our cool, wet spring.  Standing water in low-lying areas did some damage but plants in well-drained areas made exceptional growth.

We will be seeing the effects of our spring for the rest of the summer.  One of those is the bumper crop of poison ivy. Poison ivy is turning up in places were it never has grown before.

We have a forty-foot square patch of wild dewberries in a dry spot near the chicken run.  Those vines choke out anything that tries to get a foothold. Not this year though. The poison ivy has nearly overgrown the dewberries this spring.  I’m sure it was in large part due to the rain stimulating the poison ivy growth.  Poison ivy resembles dewberries at first glance.  It would be very easy for someone to walk trough that area without realizing there was poison ivy mixed in.

Notice the dofference between poison ivy in the center of the photo and a bramble leaf to the left.

Be careful when working in your yard and garden, you may have poison ivy growing and not realize it.  As a reminder, poison ivy has three leaflets growing out of a single point on the stem.  The leaves are smooth and often, shiny-looking.  It can grow as a vine, a shrubby plant or look like any other weed in the yard.  Sometimes a young Box Elder seedling is mistaken for poison ivy.  If the plant in question has thorns, it is not poison ivy.

It’s a good idea to keep in mind that old saying: “leaflets three, let it be”.

Bob

 

Keep Weeding

Here we are, well into July and have progressed this far in the garden with all of our planting,  fertilizing, controlling pests and so on.  It takes a lot of work to keep up a garden and it’s easy to get distracted by other summer time activities… the pool, the lake, golf.

Make sure you are diligent in keeping up with your weeding because weeds grow extremely fast this time of  season and can overtake your garden if you are not careful. This is especially a problem for those who take a week or two vacation during the summer only to return home to find their formally spotless garden full of weeds once again.

These weeds will drastically reduce the onion yeild unless they are removed soon.

Many garden crops cannot compete very well with weeds and need to be kept weed-free throughout the season if you hope to get a crop this fall.  Onions are an example of a crop won’t produce well under weedy conditions.

Mulching your garden will go a long way in helping to keep the weeds down even if you don’t get all of the garden covered.  If you do decide to mulch, remove the existing weeds to keep them from growing and pushing up through your mulch.

Mulching will reduce the amount of weeding that you will need to do.

There are many types of materials that can be used for mulch such as straw, shredded leaves, hay, grass clippings, paper, plastic, old carpeting etc.  The idea is to cover the soil so that no sunlight will reach the surface of the garden.  Since most weed seeds need sunlight to sprout, they won’t grow into a problem for you.

Perennial weeds such as quack grass or morning glory are harder to suppress with mulch but even they can be greatly reduced.

The main idea is  keep up with your weeding, don’t let it get out of hand and it will  stay manageable.

Bob

Poison Ivy

Judy and I have been spending many, many hours each day in our gardens. May and early June are particularly busy for us. We do have help however.

Every year we have to remind our helpers about Poison Ivy. Some learn very quickly how to identify it while others need a little more time.

If you are spending any time at all outdoors, chances are you may encounter this plant.

Poison Ivy is easy to spot once you know what to look for. The most noticeable characteristic is its three leaflets.

Notice on the plant shown below how the three leaflets look.

This is a Poison Ivy plant that has been cut back numerous times, it’s a little weak and the leaves are fairly small but still is recognizable. It almost looks like a small tree seedling.

On this next photo we see Poison Ivy in its climbing form growing up the side of a building. The three leaflets are clearly noticeable.  Also, notice how much larger they are.

Now in this case, the owner of the building wanted a decorative vine to climb up the brick wall. He went to the nursery and picked out a very nice vine and planted it. So far so good.

Unfortunately, as is often the case, a Poison Ivy plant has taken root right next to it and is over-growing the decorative vine.

If you look close, to the right of the photo,you can see a vine with only a single leaf growing habit, that is the vine the owner planted and it’s not competing very well against the Poison Ivy.

The owner insists that the Poison Ivy vine is the decorative vine he planted! Poison Ivy has the most beautiful red colored leaves  in the fall. No wonder he can’t believe it’s Poison Ivy.

There are other plants that have three leaflets, brambles such as wild raspberry are one example. Their leaves are fuzzy and the vines have thorns on them while Poison Ivy is smooth all over.

So, enjoy the outdoors but watch out for Poison Ivy and remember that old saying…”leaflets three, let it be”.

Bob