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.