As an old guy who has been in and around the green business for a long time, I've seen some changes over the years.

Frankly, one of the fascinating things that I've been able to watch is the evolution of who does yard care and how they go about it. One of the reasons that's so interesting to me is that it's still changing, and right now, at a pretty rapid pace.

I've written columns about that before, and will in the future. But today, I want to talk about changes concerning trees, infrastructure and equipment.

Years ago, when I decided to go fully into the tree business, a very large percentage of my time - and my employees' time - was taken up by working on mulberry trees. As the years have gone by, the number of mulberries out there has declined by about 90%. You might wonder why there are so few mulberries left; I'm about to explain that.

Mulberries have a bad reputation, and pretty much any time someone starts talking about mulberry trees, someone else will start talking about what a bad tree they are, and that you should never plant one.

That's unfortunate because the reality is that mulberries are really drought tolerant, relatively trouble-free big shade trees that can be depended on for a half-century or so of good service in someone's yard.

The reason they have a bad reputation is essentially twofold.

First, up until the latter part of the last century, builders used some pretty sketchy materials for sewer lines, and those lines seeped water into the soil. Naturally, when tree roots came across that water, they followed it to its source, and thus stopped up the pipe, and/or broke it.

These days, the PVC pipe that is used for sewer lines does not leak, and thus does not attract roots. The odd root may grow across or alongside a PVC line and crush it as it grows, but that's pretty rare.

Secondly, mulberry roots are well-known for lifting and sometimes even breaking concrete slabs. This is a problem that is easily avoided by not planting one right next to a house or drive.

Frankly, we should be planting mulberries left and right, but we don't, because everybody just "knows" they are bad trees. Essentially, more modern building materials, and the knowledge gained about how mulberries grow - since we used to have a bunch of them - has turned them into a very useful landscape tree, but somehow we just can't seem to get past that bad reputation that in reality is now almost totally underserved.

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Another great tree that is somewhat the victim of past prejudices is the magnolia.

Now, personally, I love magnolias. They are gorgeous trees that have very large, extremely aromatic flowers. I find them so attractive, I would still like them even if they grew large thorns along with those big flowers.

However, there are a lot of people who will tell you that magnolias are "trash trees" which drop a lot of litter.

In my opinion - and remember I mowed a lot of yards when I was a kid - the reason for this is that the lawn mowers we used to use 20 and 30 years ago wouldn't pick up or shred fallen magnolia leaves. Rather, it would just spit them out the side of the mower with a few slices in the relatively complete leaf.

In short, they had to be picked up or raked to get rid of them.

These days, the much higher horsepower mowers that are being used to mow yards do a much better job with those leaves.

Still as with the mulberries, that bad reputation - while the real problem has been resolved - still persists.