TERRY: This area around Frederick saw quite a bit of action during the Civil War.

There were three major battles fought relatively close, the Battle of Antietam, the Battle of Gettysburg, and the Battle of Monocacy, right on our doorstep.

The Battle of Antietam was the bloodiest day in American history.

There were over 23,000 casualties.

The majority of the wounded from Antietam passed through Frederick, so the population of the town almost doubled.

And almost all of the public buildings in town were taken over for hospitals.

The National Museum of Civil War Medicine takes you through the whole medical experience of the Civil War.

We have dioramas of camp life, ambulances, the field hospital, field dressing station, and a pavilion hospital set up so that you get the real feeling of what the experience actually was.

We have the only known surviving surgeon's tent from the Civil War.

It's a canvas wall tent, belonged to Surgeon John Wiley.

And he used this as his living quarters, and in the morning, anybody who felt sick would come and report to him for surgeon's call.

And then he would give them medicine if needed.

So, pharmaceuticals were very important in the Civil War.

Not only were they used for pain relief, they were used for anesthetics.

But in the South, they were getting scarcer and scarcer, so they started to look at plants that grew naturally in their environment and to find substitutes.

GREG: 200 years ago, medicinal plants were the modern drug therapy that doctors used to treat a variety of ailments, whether they were Civil War soldiers or families.

Here at the University of Maryland Extension Office in Frederick, Maryland, this is my medicinal garden bed with about a half a dozen plants that historically have had medicinal value.

Probably the most interesting plant we have here is a plant called lamb's ear, and that was called nature's band-aid.

This has a chemical in it that, actually, if you were to cut your finger, you could wrap the lamb's ear around your finger and it would actually stop the bleeding.

The other plant we have here is lemon balm.

This plant is great because if you take a leaf and you kinda roll it between your fingers and you smell or sniff it, uh, it smells just like lemons.

And this would've been used as a calming tea at the time.

The other plant we have here is a plant called sedum.

It's a big thick green leaf plant used for its immune-boosting properties.

Modern-day medicine started 200 years ago.

And the plants we'd been using really formed the basis for a lot of the drugs we use today.