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Perhaps it's the many questions or maybe it's my frequent trips to the garden, but something has convinced me that this is a great year to find unwanted insects in the garden.

First, it was the golden aphids on the butterfly weed. But that happens every year. Then it was the red aphids on the heliopsis. Interestingly, a similar plant just across the garden was unaffected.

Then there was a white worm that I had never seen before chewing on a shrub dogwood. One plant was covered and the half dozen right beside it was unaffected. I picked them off and made a pile just a bit smaller than my size 12 boot.

I also was impressed to see a horde of black and white worms gracing the cover of a national nursery trade magazine. By the next day the same worm horde was on my serviceberry. While I pondered this problem for a day or so they stripped the plant of all foliage and were then nowhere to be found.

Bagworms are eating some neighborhoods and, of course, as we approach late summer the tent caterpillars arrive. An army of beetles had fun with my hibiscus. They got sprayed.

My observation is that insect outbreaks can be quite limited, causing little damage or, in some cases, needing some intervention. My intention here is not to address specific problems but rather to offer a few generalizations.

Before you dash for the sprayer, figure out what your problem insect is. Much of successful control is related to timing. For example, summer oil does wonders on bagworms in early June but by the time you see the moving bags they are tough to get.

Most of the soft critters like mites, aphids, worms and scale can be controlled by clogging their breathing pores. Purchased insecticidal soaps, summer oils or a homemade brew with dishwasher soap will often do the job.

Landscape professionals seldom use summer oils in July and August because of potential plant damage from high temperatures.

Hard-shelled insects like beetles seem to me to resist most efforts short of spraying. As a member of the industry, I have carried a pesticide license for many years. That permits me to get chemicals that are not available to the home gardener.

Several days ago I visited one of the better-stocked garden supply stores in the area to see what controls were available to the home gardener. There was an interesting and adequate selection.

Some insecticides were synthetic and some were natural. All pesticides have a listed Ld 40, The Ld stands for lethal dose. The lower the number the more toxic the product. I mention that because some of the natural products have lower Ld 40 numbers than their synthetic counterparts.

Sometimes the sprayer is necessary, often it is not. Timing is important. Be informed before you spray. Think safety. Seek help selecting controls. Read the label. Protect the environment.

This year we again managed to displace a few more weeds with flowers. For some reason patches of annuals seemed to take precedence over additional perennial plantings so far this year.

Fortunately we still have the late summer and fall seasons remaining, which are excellent times to add perennials and woody plants. As always I have more projects than will ever be accomplished. I guess that is the case with most of us who are addicted to the garden.

As one who makes his livelihood from the garden industry, my attention is always divided between my own garden projects and what is happening on the new plant scene. What will you find in the greenhouses when you visit next spring? What mix of tried and true plants, the winners from last year's introductions and the new introductions will be there?

We are fortunate to be in quick driving range of one of the premier test gardens in the country. I am referring to the Penn State Southeastern Experimental Farm near Landisville. In addition to agronomic crops they have a major trial of flowers.

These trials are organized by the Penn State Extension Service with a lot of planting assistance from the Lancaster County Master Gardeners. Many of the top names in the horticulture industry donate the plants and pay for space in these trials.

Throughout the season the plants are judged weekly on four points. They are flowers, foliage, uniformity and over all growth. The result of this judging becomes available from the Penn State Extension Service. A few of the best ones are flagged for quick identification by visitors to the trial. If a plant has multiple flags it also scored well last year.

I failed to mention that all plants are grown in containers and replicated three times. The container growing is to minimize soil born diseases, which are quick to invade such large trials. They are grown with drip irrigation and a fairly strong fertility program. As I have said many times, the successful container needs a lot more fertilizer than the successful flower garden.

Trials like this seem to attract hordes of some of the common plants. There are more geraniums, calibrochoa, petunias and New Guinea impatiens than I can look at and appreciate the subtle differences.There are also some interesting new plants. To me the eye catchers were an apricot colored thumbergia, a new series of exotic impatiens, a new begonia series to challenge the non-stops, better coleus, an annual white euphorbia to name a few.

A few years ago thumbergia arrived as the black-eyed-susan vine. My daughter had a hand in the new impatiens. The euphorbia will not reach widespread distribution for a year or so.Landisville is close and if you like flowers this trip would be a few hours well spent. They are open to the public, free, easy to find and you can wander at your leisure.

To get there I take 222 to 741. I follow 741 to the Old Harrisburg Pike. Instead of taking a right to Park City I head left through Landisville.

Past Landisville you hit a near dead-end stop sign and must turn left on Esbenshade Road. You quickly cross over 283 and immediately find Auction Road on your right. Follow Auction Road to the stop and small signs will lead you for the last half mile. You will see flowers before you figure out where you can park.

As our preacher said Sunday - GO, but then I guess he wasn't talking about flowers.

Why is it that often an insignificant event from long ago remains a vivid part of our memory? Such was the time that I used a small John Deere diesel to yank out an old weigelia bush that my grandmother had planted.

That tractor lived with me from 1967 to 1991 and that bush was one of its earliest acts. I plainly remember this scraggily bush planted in back of the springhouse and flanked by the gas tank on one side and the diesel fuel tank on the other side.

Perhaps I was seized by the urge to destroy something and start over. That is an all too common desire in the garden. Often we would be better off if we thought about it a bit more before we engaged our start over gear.

More likely the bush was old, beyond rejuvenation and just plain ugly. It was the only one of my grandmother's gardening efforts that I never liked. It was so bad that I vowed then to never plant another weigelia.

One of my favorite gardening truisms is that you don't know how to grow a plant until your know how to kill it. I guess a good corollary to that rule is how can you be sure you don't like something if you haven't planted it.

Anyway, about three years ago three different weigelias returned to my garden. In the many years since the destruction, the plant breeders and selectors claimed that this shrub was greatly improved. To paraphrase the words they used, they were smaller and tidier than the weigelias of yesteryear.

I planted them in a spot where I see them every day. Several days ago I paused in amazement to admire the multitude of flowers on one of them. Weigelias are supposed to yield a heavy spring bloom and then flowers sporadically throughout the rest of the summer.

The variety in question was one called French Lace. It has very red flowers and green foliage with bright yellow leaf margins. To me that sounds awful on paper but in reality it was one of my most breath taking sights of the summer. I confess that I have lots of them.

The most widely planted weigelia is a dark red foliaged one called Wine and Roses. This year it was joined by a much smaller version called Summer Wine. The latter is supposed to stay under two feet. There has got to be a spot for that one in my garden, too.

Most of today's weigelias are listed for heights of under five feet, quite a bit shorter than those of years ago. They will thrive in most soils if they get plenty of sunlight.

The literature also suggests that you remove dead tips in the spring and prune to tidy up their appearance. True to form, and in all honesty, I have yet to touch the three I have planted. That suggests that despite being in a very cold and windy spot I have had little or no tip dieback. Also, the plant's habit in the first three years has not needed the shears.

I lost grandmother and her wealth of gardening experience at least ten years before I destroyed her weigelia. I trust I will be forgiven. I will always benefit from her influence and am glad that I have rediscovered weigelias.

Recently, the governor of Connecticut signed a law banning the sale of over 80 plants that supposedly are a threat to the environment, including many that are lurking in the nursery trade. A few weeks later he resigned his office. The two events were not related.

I have not seen that list yet, but many in the industry feel that the new law greatly overstates the problem. Similar, but smaller bans have occurred in several other states. Discussions are occurring in many more. The point is that gardeners and the nursery industry must be sensitive to the problem of invasives or risk additional bans.

Last week I mentioned purple loosestrife. Next on the hot list are several grasses. One is Chasmanthium latifolium or Northern Sea Oats. This is a grass that is several feet tall and sports a heavy seed head that somewhat resembles the grain oats. This native grass is a good groundcover for difficult sites.

Its problem is similar to loosestrife in that it wants to migrate to moist thickets and creek bottoms. The seed is heavy and never falls far from the plant. It you pull it just as it emerges in the spring, it is easy to control. If you are a few weeks later its roots seem to reach the center of the earth.

The other grass is the large group of Miscanthus. That is the one with the large, often white, puffy fall plume that is quite common in many gardens. Varieties include Morning Light, Zebra Grass and probably at least 50 others. Often it will be referred to as Japanese Silver Grass.

If you drive Route 1 deep into Chester County, you will see Miscanthus activity on the road banks. I have not been able to determine if it was planted or has arrived on its own. This does have the attention of the invasive watchers and many of the native plant advocates.

Many of the Miscanthus are reported to be sterile and I have only seen occasional seedlings from the old time cultivar, gracillimus. That one has sharp narrow green leaves. Grandma even had that one.

The next one will come as a big surprise. Butterfly bushes are on the "be careful with" list. As we all know, in order to thrill both the butterflies and us this plant produces a constant stream of flowers from July to frost and probably several zillion seeds. However, the seeds are fertile and you should be ready to destroy unwanted seedlings. Recently I became aware of a research project at Longwood Gardens with the goal of breeding a sterile butterfly bush. To date they have not succeeded.

The common yard tree, Norway Maple and the erosion control shrub autumn olive also are threats.

Interestingly, it is assumed that the most feared garden thugs are those that spread by underground roots. Yet the most talked about ones in southeastern Pennsylvania are all the result of seedlings.

For a short list of plants with underground roots or stolons that could cause problems I would include obedient plant, running bamboo and gooseneck loosestrife. A second interesting observation is that thugs in your garden may be well behaved and just the opposite in mine.

My point. As gardeners and nursery professionals we must police our gardens and ourselves. If we don't, there are interest groups that will lobby for more rules that will be made by people who seldom get dirty or know how to sweat. My guess is that their solution would be worse than the problem.

If I look straight out my windshield at the last red light on my way home, I spy a tall stately perennial with a purple flower. I saw the same plant on my last summer visit to New York State. There you could look out any window and see this beautiful plant for mile after uninterrupted mile.

Of course I'm talking about purple loosestrife. This beautiful plant can be a thug and bane of the natural landscape. In fact, it has turned islands in the nearby Susquehanna River into near jungles. It is bad enough that the researchers are trying to introduce natural predators (loosestrife eating insects) to slow or reverse this plant's advance into our native landscape.

The plant, I believe, has disappeared from the nursery trade in the last five or 10 years. It has been long enough that I forget the cultivar name. It may have been Robert's something. It was represented as sterile.

I had it in my garden until five or six years ago. I can verify that it was only near sterile and that occasionally seedlings escaped. These seedlings appeared to be more vigorous than the mother plant.

I never viewed it as a problem, but then I had it planted high and dry. Those conditions are the opposite of where it is a problem. It loves to take over wet areas.

In my garden it was so pretty that everyone wanted to buy one, so I finally destroyed it to avoid the hassle of telling people that it was no longer available. I am not positive that its sale is banned in Pennsylvania, but I am sure that the plant police from the Department of Agriculture are on the lookout for it in nurseries.

Usually I write these articles in one frantic burst as I rush to meet deadline. However, this week I got started three or four days early. Ironically, a few hours after writing the first several paragraphs I found myself face to face with a rather large and nasty looking patch of loosestrife near where the headwaters of the west branch of the Octoraro crosses the remains of the low grade railroad.

It was the first time I had seen a wild stand of loosestrife in the area away from the Susquehanna. To me that was a sobering sight. My fear is that in a short time purple loosestrife will filter down that scenic valley at the expense of the native plants.

I realize that the above will spark the debate about what to plant. The advocates of natives will say only natives. Unfortunately, that is but a small part of the palette that is available for our gardens.

The other response is to be careful with the plants that find their way into our gardens. Here the nursery operator and the gardener both have responsibilities. Stay tuned for some more friends or thugs next week. You will be surprised at some of the suspects.