365 Urban Species. #166: Multiflora Rose

[urbpan]

Comments

[ritaxis]

I have a friend who lives in Revere and she's been telling me about these roses. I've always had a hard time visualizing them. Now I see their flowers are nearly identical to a named rose (Kathleen?) which is in our garden -- it's not invasive here (It's a little pushy in growth habit but it does not reproduce itself, and in fact is subjugated by the flowering quince and a different rose). I imagine our rose has the multiflora in its parentage, but it's not the same rose -- ours has a longer blooming season, and in fact is remontant. Still, I wonder what makes it invasive in one area and docile in another. Cold winters?

[droserary]

It really depends on the species. The invasive mile-a-minute weed (Polygonum perfoliatum) requires a substantial period of cold in order for germination, so it has mainly been spreading throughout the Northern US states. Others seem to hate the cold and die back in the harsh Northern winters. Still others (like Ailanthus altissima--the Tree of Heaven) don't seem to care that much about cold winters, water availability, or even high levels of pollution. In other cases, it's not the weather at all, but the ecology of an area. While cordgrass Spartina alterniflora is native to East Coast tidal marshes, it's considered the single most dangerous plant in the West Coast because it's completely destroying the native tidal marsh ecosystems over here

[ritaxis]

Thank you. I've been thinking about that all day, how roses of all sorts do establish themselves in little spots but do not spread. It seems to me that one important clue is that roses hardly go dormant here. Some just don't: they bloom and produce new leaves all year, only slowing down a little. I do believe this is not just choice of variety: I believe I have seen mention of roses grown elsewhere that go dormant in those places and not here.

So I was thinking: what if that's crucial to the roses' spread? Like we have all these species here that don't germinate without fire. Do rose seeds have to be traumatized to germinate?

Multiflora rose

[ritaxis]

While "naturalized" has several different meanings, from an ecological standpoint it is most often used to indicate whether a species can survive on its own outside of cultivation. There are plenty of non-native, naturalized plants that spread on their own but are not considered invasive. I know, you probably think I am splitting hairs here. But the difference between invasive and naturalized would be the harm to the ecosystem, which admittedly can be hard to prove

[browntreesnake]

I use the Global Invasive Species Programme's definitions:

Alien/exotic species: any species that is not native to a specific ecosystem.

Invasive alien species: an lien species whose introduction does or is likely to cause economic or environmental harm or harm to human health.

Factors that can make a "good" invader include rapid growth rate great dispersal capabilities, larg reproductive output, and broad environmental tolerance.

[stephanietberry]

A (multiflora) rose by any other name would still cut you to pieces and take over any forest borderland, meadow, or yard that it could.

Have a lot of problems with this!

[anonymous]

There was one in my mother's back yard that nearly took over the entire yard! It had to be taken out when a neighbor's leaf fire got out of control and the plant was damaged. We had to have it done by a professional; the main tap root was more than a foot in diameter, and the vines had rooted themselves and started new plants. I have the same problem at my house. But it does provide shelter for the birds and rabbits, so I'll wait until fall, when the vines go bare, to remove it. It's collapsing in on itself, and the birds won't nest in it anymore.

[bothwill]

You have a special way of talking about flowers, it's obvious you're have a really passion for them and understand their beauty more than most people do. As for me, nothing compare with a red rose, that's the ultimate flower in my vision.