Feb 5 2012

First wild bees of spring!

Presumed Lasioglossum bee visits bok choy on February 5

Presumed Lasioglossum bee visits bok choy on February 5. Honey bees were also busy, and one is shown for size comparison.

Even though it’s only February 5, the unusual warmth has brought out flowers – and now bees. Honey bees have been out all winter, but these are the first wild bees of spring.

This little gal (on the left) is working on bok choy in my garden. A honey bee, which was also working on these blossoms, is included on the right side for size comparison. This irridescent greenish black bee, is likely a lasioglossum, though I can be sure, because I can’t see the wing veination. It was sunny this afternoon with some clouds scuttling along, got up to 83F. It was quite breezy, so was very difficult to get a clear shot.

First Xylocopa virginica of 2012

First Xylocopa virginica of 2012

I hate to post a blurry photo, but the wind was whipping the plant and focus was very difficult. This gal got spooked by my presence and flew off after this shot. But it does make proof that the eastern carpenter bee was out at this extremely early date. I always have said, it’s not really spring yet, until you see the carpenter bees.

 


Jun 15 2011

Just started: new garden blog!

As an avid gardener, much of my writing is on garden topics not necessarily relevant to this page. So I’ve started a new blog, GadenSouth at http://gardensouth.org/ Gardening in the South presents some unique opportunities and some unique problems, and not all of these are well covered in garden literature.
I’m always experimenting, so this should be an active blog. There will be overlap, and I considered posting duplicates, but then decided to link, so look on the right hand column for articles relevant to both gardening and pollination or bees.

May 18 2011

A simple explanation of tomato pollination, please?

Most plants in the wild are self sterile, ie. Nature dislikes incestuous propagation and prefers cross pollination, where the pollen is transferred between two genetically different plants. Cross pollination is achieved for most vegetables by an agent (called a pollinator), that physically moves the pollen. Usually this is a bee, because they are specially equipped to efficiently carry pollen; they are brawny, fuzzy, and have a static charge, so they acquire and transfer many grains of pollen.

In the case of the tomato, mankind has (perhaps unwittingly) selected plants with the defect of being self fertile. This likely came about as the plant was moved from its native area to other parts of the world without moving the native pollinators that were best equipped to cross pollinate them. So the surviving strains were the ones that had this defect.

Looking at cross pollination from the point of view of the fruit grower is utterly different from the point of view of the seed grower. With most plants, good cross pollination is very much desired, in some cases to make fruit at all, and in other cases to cause better quality fruit. Of course uncontrolled cross pollination makes the seed grower nuts, as he cannot predict exactly the characteristics of the plants grown from the seed.

Tomatoes are kind of a dream plant that can function both for the fruit grower and the seed producer. The reason is that they exhibit little “inbreeding depression.” That is, most plants, if they have any self fertility at all, will grow puny fruit and poor quality seed.

Tomatoes can be self fertilized and still be fairly vigorous.

In a discussion like this, someone always pipes up with the claim that tomatoes are “self pollinating.” This is a myth. Remember that myths are half truths. Most of the time, when you hear the myth, it is, of course, in the context of why tomatoes AREN’T self pollinating. Odd, isn’t it?

Most flowers have anthers (the male organ) that have the pollen on the outside. Anything that brushes the anther is likely to pick up some pollen. Tomato anthers are different; they are hollow tubes with the pollen grains inside. They are not released to the touch. The tomato must have help. It requires MOTION to release the pollen. Wind can accomplish this to some extent. Pollen grains are shaken loose and may land on the sticky stigma, thus accomplishing fertilization of some of the seeds.

Note that this is not self pollination, as the tomato could not do this of itself.

You can hand pollinate tomatoes by using any means of shaking the blossoms that doesn’t break plant parts. You can tap on the stem below the flower cluster with a pencil. Or you can hold an electric toothbrush against the stem. But the best tomato pollinator is a bee that “sonicates” or “buzz pollinates” the flower.

Sonication (Buzz pollination)

Bumblebee on a tomato blossom

Bees, most often bumblebees in eastern USA, will land on the flower, pulling it down until the anther is vertical (thus getting gravity’s help) and then vibrating their wing muscles (and their entire bodies) to shake loose the pollen. The vibration causes the flower to resonate, and many grains of pollen are shaken loose. This drops onto the bee’s belly, which is also vibrating. Some of it will stick to the bee and be available for cross pollination when she visits a flower on another plant.

Much of it will bounce right back up to the sticky stigma.

The development of the fleshy part of the fruit is stimulated by the fertilization of the seeds. Pollen grains on the stigma grow pollen tubes to the incipient seeds and fertilize them. If only a few grains of pollen are delivered, a fruit may form, but will not size up.

When enough grains of pollen are delivered to fertilize most of the incipient seeds, the fruit will be all that it can be.

If you are growing tomatoes for fruit, and not for seed saving, cross pollination is not of much concern to you. You just want good pollination to get the most and best fruit possible.

If you are growing tomatoes for seed, then you want to control the pollination more carefully. Generally, a gardener who saves seeds would want to keep an open pollinated variety pure, so you seek means to isolate the plants. This can be done by excluding bees (cages around plant or flowers), by sufficient distance between plants, or by timing bloom at different times.

Some tomato varieties are even nicer to the seed grower. The pollen is viable, even before the flower opens. If the flower gets sufficient motion (one reason why gardeners intuitively love early morning thunderstorms), it’s possible for the seeds to be fully fertilized quickly and keeping cross pollination down to a bare minimum.


May 18 2011

Turning our place into a bee sanctuary has paid off big-time!

No blossom drop!

Every flower in the cluster set fruit.

In many years, I’ve not seen tomatoes set every blossom, as they have this year. There are few of the blossom clusters with a “hole” where there is no tomato forming.

I’ve been exulting each morning as I watch the bumblebees “buzzing” the flowers. As they taper off, and go to other flowers, they are replaced by little flying emeralds – the tiny, in-your-face green bees that happily gather the remnants the bumblebee left.

Not everyone is aware of the debt we owe to the bees. Pollination can be the limiting factor for many crops, including tomatoes. I have had years when I added compost, adjusted the pH with lime, fertilized, and carefully weeded the plants I set out, only to see many of the blossoms drop off, and the total crop wind up a sorry one.

Tomato flowers do not give the bees nectar, only pollen, but this pollen is gathered by the bees for the nutrition of their young. As they do so, they make a trade with the tomato plants by aiding the fertilization of the seeds that will make next year’s crop.

In another blog post, I’ll discuss the mechanisms of pollen release, which is different for tomatoes than most crops, as well as discuss the popular myth of “self pollinating” tomatoes.

But for now, I just simply want to rejoice and enjoy the fruits of the labors of my little friends.


Apr 22 2011

Earth Day 2011

Why do I observe Earth Day?

In what is regarded as the oldest book of the Bible, a wealthy man, Job, is stripped of his wealth, furthermore he loses much of his family and his health.

The book is commonly regarded as an answer to the reason for evil in the world. It also speaks clearly to the role of humans in their environment.

After Job’s complaints about his losses, God speaks (Job 39) and “puts him in his place.”

He says, “Where were you when I laid the earth’s foundation? Tell me, if you understand.
Who marked off its dimensions? Surely you know!
Who stretched a measuring line across it?
On what were its footings set, or who laid its cornerstone — while the morning stars sang together and all the angels shouted for joy?

God goes on to give many examples of things in Creation that are beyond Job’s ken and control. He says, “Does the hawk take flight by your wisdom and spread its wings toward the south?
Does the eagle soar at your command and build its nest on high?

Contrary to modern man’s prevaling idea, we are not the masters of the universe. We look around and feel a sense of awe at what we see. The Pagan looks at the universe and worships it. But Job shows us that it is the Creator, not the creation, that is the object of true worship.

The Psalmist (chapter eight) says: “What is man that you are mindful of him,the son of man that you care for him?
You made him a little lower than the angels, and crowned him with glory and honor.
You made him ruler over the works of your hands; you put everything under his feet: all flocks and herds, and the beasts of the field, the birds of the air, and the fish of the sea…

We have a role to play in the management of the creation. But that role is contingent upon our relationship with the Creator.

The Secular Humanist claims that environmental destruction has come from the Judeo-Christian idea of the dominion of man. While there may be Jews and Christians that have participated in the rape and pillage of the planet, the charge totally ignores that much of the worst damage has been done by those who oppose and reject the Judeo-Christian heritage. The charge also ignores that the environmental movement has its roots in modern Christian cultures.

Modern man is incredibly arrogant. We think we are at the pinnacle of accomplishment, and all is now within our control.

When a catastrophic leak of an oil drilling platform in the Gulf of Mexico caused massive damage to the ecology, President Obama promised to restore the Gulf of Mexico to “better than it was before.” The arrogance of such a statement can only be overshadowed by its ignorance, and it’s amazing to me that it attracted so little attention.

The solution to the environmental problem, and the placing of Earth Day (really every day) in proper perspective lies in humbly returning to the very first commandment ever given to humankind – a commandment that was given long before the famous Ten.

It is simply God’s instuction: “Tend My garden.”