JARS v41n2 - The Ross-Boge Rhododendron macrophyllum Expedition - 1986

The Ross-Boge Rhododendron macrophyllum Expedition - 1986
Dallas Boge
Gales Creek, Oregon
Part of this article was originally printed in "The Rhody Runner", the Tualatin Valley Chapter newsletter

Preliminary Trip - Early June
Bob and I had been looking forward to 1986 as a chance to explore undisturbed territory. We had planned to look at lower elevation plants, about 2500 feet, since they seemed to have resisted the June 1985 frost and had a good bud set. Consequently, we planned to go one week earlier than in 1985. This decision must of necessity have been made several months prior to the actual time, to allow us to arrange our respective schedules.
Part of our plan was to go up a couple of weeks before the actual time of exploration. We chose to go on June 2, to assess the condition of the bloom.
We were not greatly surprised to find the blossoms at Detroit in full and past bloom. About two miles up McCoy Creek Road we stopped and took a walk into the woods in a large population of blooming rhododendrons. There we ran into two major disappointments.
First, the plants were in full bloom. For our timetable to work they should have been just starting to open. A second and more sinister situation slowly became apparent. Ants were crawling all over the blooms emasculating them as fast as they opened. We hoped without any great conviction that this was just a local problem. It wasn't.
Journeying on to "Rhody Flats" only confirmed that the blooms and ants were widespread. Everywhere we went we found blooms and ants. Even over on the top of Boulder Ridge, the highest (4100') population of Rhododendron macrophyllum we knew, we found the little black crawly emasculators at work on the already open blooms. Not everything was in full bloom, but it was two to three weeks ahead of last year. It was looking more and more like our expedition in two weeks would be spent viewing lots of faded blooms.
It was time to look for some new areas to explore. We took off on a road leading east of Boulder Ridge. Here we found R. macrophyllum growing up to an elevation of 4800', higher than they are supposed to grow. Of course, they were also in bloom! After checking a few of our 1985 finds, we headed home, not too optimistic about 1986's prospects.

1986 Explorations
1986 seemed to be off to a good start. We got into our reserved camping space beside Detroit Lake on the first try. Although it was raining lightly, and showed no signs of letting up, we were anxious to get to our task of locating exceptional plants.
Even though we had come a week earlier than the year before, our preliminary trip two weeks before indicated that we would only find bloom at the upper limits of R. macrophyllum's range. Since we were most interested in seeing 85-27 in bloom we headed up to Boulder Ridge first thing. 85-27 was in tight bud, but all around it there were many plants in full bloom, so we started our new year's search right there.

It wasn't long before we found 86-1, a nicely colored 2" frilled flower. A couple hundred yards further through the wet brush we ran into 86-2, a 6-lobed flower 2" across, but completely without spots. (We were to see a number of 6-lobed flowers scattered around; this must be a rare but not uncommon aberration).
Further tromping around in this large plant population yielded 86-4, a really attractive truss of 2" flowers with 24 flowers per truss and a truss measuring 7" across by 5" high, the largest truss we had seen.
Returning to the pickups, I heard an unmistakable hiss coming from a rear tire. I asked Bob if he could hear it, but he couldn't. We went on east of the Boulder Ridge, searching for a place to look for rhododendron. We walked through several populations of rhododendrons without finding anything of interest. We then journeyed up road 630 to the end, still looking.

Parking beside a stream, we got out and again I heard a hiss. This time Bob heard it too. By now the tire was noticeably lowering one corner of the pickup. We changed it and proceeded to the end of the road, where we found a large population of very pink R. macrophyllum .
In a few spots, the caterpillar used to build the road had shoved brush off the side of the road, making large, clean, flat spots. There growing in great profusion were hundreds of R. macrophyllum seedlings. We used some of the pots we had brought along and acquired a number of plants to be used as rootstock for later grafting.
I was getting a little nervous about running around on these back roads without a spare tire, so we went back to Idanha to a garage to get the tire repaired. A very congenial man ran the only garage in town, and he quickly fixed it. I didn't know then how lucky I was to get the tire fixed, since we went by there every day afterward and he was never open again!
The next morning we headed up Santiam Pass to see if we could find an area not explored that might have some bloom. On our way back down we turned off the side roads and finally found a very steep hillside with blooming plants. We climbed to the top without finding anything of interest. Starting down a particularly vertical portion, we spotted another flower completely without spots. It was not particularly attractive, but since it was a good 20 miles from 86-2, we collected it to have as many diverse genes without spots as possible.
Wednesday was winding down when we decided to take another road previously untraveled. Six miles up from the Santiam Highway, we hit pay dirt. I walked off the edge of the road and headed down the hillside about 50' when I stooped to pick up a small plant and its one truss which was beaten down by the recent rain. When I looked into the bloom, I almost gasped in surprise, here was a spotted flower that looked just like R. irroratum 'Spatter Paint'. It soon became 86-6. Bob was just across the road, having equally good luck. He had found a flower with a red rib in the corolla, the balance of the corolla being nearly white. The overall effect was that the flower looked just like a peppermint candy, and it became 86-7. After three mostly fruitless frustrating days we had a place to look. And the weather was looking better!

Thursday morning we were back and began our search through the woods. We found several very attractive clones. We then found 86-10, a truss with mostly 7-lobed flowers. The 7-lobed flowers had 13 stamens, the 6-lobed 11. (This was true of all of the 6-lobed flowers we saw, over a wide range.) That afternoon while exploring a clear cut we found 86-12 with 3" flowers and a truss 8" across, both a new high for us. The truss was weather beaten and we could not determine its height. The rest of the afternoon was spent climbing to the top of the clear cut and down again through the adjacent woodlands. Several more very nice clones were collected.

Since our reservation at the park expired at 2:30, we had only the morning to explore. We stayed close to the pickups and looked further down the bank at the plants scattered there. This area proved one of the most productive and most inhospitable of all the areas explored in the two years of our work. We managed to pick out 3 of exceptional beauty and size among those growing there.
This last area, like Boulder Ridge, has proven exceptionally rich in good clones, and the area needs to be explored further in the future. With a favorable season next year, we shall probably spend much of our time here.

Return Visits - Fall
Bob and I returned on September 3 for a one day trip. Our primary purpose was to collect seed from Lilium washingtonianum ; we had found a large population of them this year. After collecting a large amount of seed, we had time to do some checking so we went back up McCoy Creek Road to relocate some of the 1985 finds.

After tromping around for a while 85-1 was relocated and the layer checked. It had not rooted. Directly across the road is 85-8. We had made two layers and both seemed to have rooted. We will probably cut them loose from the mother plant next year and may bring them down in the fall, if they do okay.
Our final trip for 1986 was October 8. We went to collect as much seed as possible, to check on the condition of the plants, and to bring a few more seedlings home.

Our first stop was in the area that had yielded such a rich treasure earlier in the season. The last seed collected in the area came from 86-15. While collecting, we noticed that a very rotten log lay at the base of the plant. Growing in this moss and log were a number of seedlings. Seeing the chance to experiment, we removed a patch of moss and tapped about a half capsule of seed on the semi-bared rotten log. The other half capsule was spread directly onto the undisturbed moss. We then took plastic stake labels and made brief notes of each experiment, leaving the labels stuck in the log. Time will tell if this produces usable seedlings.

We went back to 85-4 (Bob has named it Big Mac) and found one of the layers rooted. Nearby, another plant caught our eyes. It will bloom for the first time next year. Its one bloom bud is much larger than those on 85-4. We took cuttings and labeled this plant 85-4C.
Late afternoon found us on Boulder Ridge collecting seed from 1985 and 1986 plants. Our final plant to collect from was 86-4, which has the best large truss we have ever seen on an R. macrophyllum . The plant is located just off the road. We have excellent locating information (bearing and range from road signpost) but after 45 frustrating minutes we had to reluctantly abandon the search.
1986 was a year of great discoveries, but ended as it started, on a note of disappointment.

Dallas Boge is currently President of the Tualatin Valley Chapter and active at both the Jenkins Estate Garden and on the Cecil and Molly Smith Garden Committee.

For the first year's report "The Ross-Boge Rhododendron macrophyllum Expedition" see ARS Journal, Vol. 40:2 (Spring 986).