Hi Val, If the root stock is Multiflora, and it it is used by some rose growers, you should remove it. There are two reasons why. One is, it may look cute now, but it is a rampant grower. Two which is more important, is that it is the rose that is the host to a mite that causes Rose Rosette disease. This horrible disease has been discussed many times on the rose forum. As far as I know, we don't have any cases of it in our area yet, but it is probably only a matter of time. The mites travel to Multiflora plants, but then will attack other roses nearby. Rosette cause growth that is called Witch's Broom. It is an ugly disfigurement of the plant. It is an incurable. All affected plants must be destroyed. Then any plants not affected in the area, must be repeatedly sprayed with an expensive mite killer to keep the disease at bay.
The Hybrid Tea with the white bloom could be a sport. If the bloom is coming from its own cane that is attached to the plant not from down in the ground. If this is the case, keep an eye on that cane and new canes from that cane, and see if the subsequent blooms keep the lighter color. If they do you can try to make a new rose plant later in the summer. (If you know how to do this, sorry for the explaination.)Get some rooting hormone. Cut some stems, you want to do a few because usually not all will survive. Cut them long enough to have a few inches below soil level and new growth above about 8-12 inches I would guess. Remove any leaves that are toward the bottom that would end up in the soil, and if there blooms attached, remove them. Scrape a bit of the outer surface from the bottoms of the stems and dip in rooting hormone. Stick it in a pot and keep it moist. When I've done this, I've kept the pot in a spot that only gets morning sun. As long as there is green, they are ok. Once you see new growth, they are developing roots. You don't want to keep them overly moist once growth has started, just treat them like any other potted plants. Then later in the fall, you can plant them in the garden. I hope that made sense, lol.
Remy

I may be mistaken as to what the rootstock is. Last night we were out in Appleton and I saw lots and lots of rosa multiflora close up. What I have doesn't seem to resemble it all that much. The flowers are about three times the diameter, if not more (3"-4" or so across). The branches don't have the eighty million prickly thorns of r. multiflora either (my husband kept brushing against it), in fact it has few thorns. I've got a picture, I'll try to post it later when I can upload it. Whatever it is, it seems to be a rambler, it manages to hold on to things (like the air conditioner condenser), it's a creamy white color, it has five individual-looking single petals that each scallop in once at the center of the outside, kind of heart-like. It has pronounced yellow (I think) stamens. Blooms tend to be short-lived (at least in the hot heat they were), and the (rather pointed) buds are clustered. The canes have very few perioidic thorns, which hook away from the new growth in a slight curve. The stem is smooth, with a little red. The leaves are a dusky green -- almost a touch of bluish to them (blue like when we say a hosta is blue, not bright blue delphinium blue or poppy blue)or grayish, not bright or deep or glossy.

It fell out of favor as rootstock a long time ago, but could this be the dog rose? It really does not look like the r. multiflora from last night. Like I said, the rose came from the Buffalo and Erie County Botanical Gardens Rare and Unusual Plant Sale of 2000. It was from a nursery in Java or Java Center, and came in a large pot. (Beaver something or other, maybe? Beaver Meadows?) It had no indications of who grew it originally (J&P, Star, some other nursery, etc.), which might have given more of a hint, unless they're suddenly growing their own grafted roses in Java. It's not Doc Huey, so it's not a J&P. It's looking unlikely that it's r. multiflora, unless that plant varies wildly. It's not the rose I moved, either, which has small, deep pink multipetaled flowers, round buds, almost no visible stamens, etc.

Here's a picture of the rose.

Here is a link that might be useful: {{gwi:1224764}}

Hammerl, send your pic to the Roses forum or the Antique Roses forum. Those folks should know...

I tried "name that rose" yesterday, and two individuals immediately said (without my asking it) that it was rosa canina (dog rose). Thanks.