His tools include a sketching pencil, a pad of paper, a watercolor set, watercolor paper, and a squirt bottle. His subject? The natural world, whether it is Mt. Mitchell in western North Carolina, the view he sees from him home in Celo, or perhaps New Zealand. His work as an artist takes him around the globe.

Thirty of Johnson's works go on exhibit Sept. 26 in the Eleanor Smith Pegg Exhibit Hall at the newly opened Education Center at the North Carolina Botanical Garden. "Notebook Pages from Nature" will run through Dec. 21.

Johnson sketches in the field and then brings home his notebooks and develops paintings from them.

"The notebook pages have really turned into a more finished product over the years, and I sell those too," Johnson said. "Now I spend more time on them."

Prior to 1972, Johnson said he painted huge rectangles on big canvases. but then he moved to the mountains.

"The overwhelming thing out here is the natural environment," he said. "It drew me to it slowly and drew me away from what I was doing,"

For the large works on canvas he eschews the watercolors he uses in his journal and paints with acrylic and oil.

In the early19 90s, Johnson took a class in botanical illustration at the Botanical Garden.

"But for that you have to count how many parts a flower has," he said. "Mine are sort of more roughly done."

Rough or not, his work is highly prized. One of the pieces in the show is called "Signs of Spring Across North Carolina," a 36-by-52 inch composite all the different places Johnson went in North Carolina this past spring, from Ocracoke to Mount Mitchell.

Ken Moore, who retired in 2003 from his position as assistant director at the Garden, is a good friend and student of Johnson's. A trip to the Blue Spiral 1 gallery in Asheville in 2000 with his wife Kathy Buck led Moore to Johnson. The gallery represents Johnson and was showing pages from his nature journals.

"They were really incredible because they were not just of plants but insects, birds, and then there were these landscapes, like a habitat, that these individual sketches were a part of," Moore said. "Each page seemed to relate a story about a particular place or a part of a place. Wow. It was amazing."

Moore's fascination led him to take a Drawing in Nature class from Johnson in 2001 at the Penland School of Crafts. In it, not only did Moore learn about a technique that Johnson had developed to reproduce color seen in nature in one's journal, he also ended up assisting Johnson by helping students with plant identification.

A great bond was formed, with Moore assisting Johnson with two more classes. He will co-teach a workshop with Johnson at the garden on Sept. 25, 26 and 27.

"The wonderful thing about Robert is that he is so unassuming, so down to earth," Moore said. "He doesn't think he is anything special. I think he is a genius."

The technique that Johnson developed uses a color chart he created. If one is out in the field and sees a flower that is blue, one looks for the same shade of blue on the chart and writes its code in the journal. After returning to the studio one can look at that number on the chart and find instructions on which colors to mix to get that hue. Included in the workshop is a kit Johnson has put together with all the tools needed for his technique.

Johnson hopes that his work, whatever it depicts, instills in students and in viewers the knowledge that the natural world is rapidly disappearing.

"Getting out to these beautifu lplaces, I feel like I am being a witness to these places that are becoming less and less, that are changing by getting overused," he said. "Like in North Carolina 10 years ago, there were places that were really remote and now are being used quite a bit. They have a whole different feel to them."

Moore has heard his call.

"Robert has given me a gift that is to help me build my own instincts of taking a closer look," Moore said. "He has affected my whole way of going outdoors."

To register for the workshop, call 962-0522 or go to www.ncbg.unc.edu.