I would tend to agree that as a prairie matures, the QAL should diminish. of course then it turns into a vast stand of canada goldenrod ;-) there are succesional weed species and qal is an early one ....

It depends what you mean by a 'nurse crop'. This term usually refers to a short-lived or non-aggressive species (usually an annual) that is planted intentionally to reduce erosion and weed infestation, with the expectation that it will gradually be replaced by the desired species.

If that is what the park personnel are suggesting for QAL, I don't think it is a good idea. No sense adding a known problem when you could use more appropriate species such as annual grasses. I suspect that what they really mean is that QAL is not a major long-term problem as a 'weed' in robust prairie plantings. That it tends to be out-competed by the desired prairie species. But still no reason to introduce it into the mix intentionally!

Nurse crops are not always intentionally planted. We use both Kochia scoparia (ironweed) and Salsola spp. (russian thistle) as nurse crops. We do not intentionally plant them. And yes, they are can be extremely agressive and persistant under the right conditions. However, knowing that they are also successional plants and out-competed by native species in the 3-5 years it takes our reseeding to establish allows us to take advantage of the natural cycle instead of spending gobs of time, energy and chemicals to control something that most times does not turn into a problem.
April, how far along is your little prairie? If it's still establishing I wouldn't stress near as much as if I was dealing with a new invasion in a older, established prairie.

Hi Rosa and John,

The ranger's don't plant additional QAL, but they also don't bother pulling it up or putting round-up on it. What's there is what's there.

Rosa, this will be the little prairie's second spring. And I had a heck of a lot of QAL last year!

ah, the ol' nurse crop question again...

is QAL a nurse crop or not?

first of all, QAL is a biennial primarily. first year rosette and 2nd year flower is the typical habbit. so by working back in time, one can tell how well the innitial prep work was. if u have a 'heck of alot of QAL last year!' and that year was the first year after innitial weed management (prep work), it tells me that u didnt get everything during that prep work. and that also tells me that there might be much worse things lurking...

but with that said, back the question at hand, is QAL a nursecrop or not? biennial is weaker than a perennial. and an annual is weaker than a biennial. so i guess in the whole picture, its not as bad as some but much less desireable than others, in terms of nursecrop function. i fall into the camp that QAL has some benefits to wildlife and it is reasonably weak in persistance. nature abhors a vacuum and something is gonna show up...QAL is (imo) relatively low on the scare scale.

lastly, QAL can be managed by mowing the flowerheads. if one is concerned about QAL population desity, then a simple weedwacking of flowering plants 1 time a year @ year 4,5 and 6 will cause a heck of alot disruptions to populations. roundup use is very unwise concerning control of QAL in a prairie.

froggy

Yes, as a biennial it is fairly easy to control by mowing. The rangers are wise not to use chemical for control in this case. QAL not something I would particularly want in a native prairie but it does serve a function and butterflies love it! It sounds like they are keeping an eye on it and it's just not a problem.

Do a little maintenance as froggy suggests to eliminate seeding. And be glad it's not canada thistle that's in your prairie!! Really, it will be gone in a few years when the natives can compete.

Froggy,

I prepared the site thusly. I roto-tilled it in early spring and applied round up 3 times over the course of the summer, 2 years ago. I HAD to roto-till it, unfortunately, as the soil was like a brick. It had been a children's play area and foot path, previously. Obviously, the rototilling disturbed the soil and caused a lot of seed to be exposed to light/the elements and germinate. I seeded and raked in the native seed in late November of that year.

Last year, my prairies first growing season..there were lots and lots of QAL. I mowed once, when everything got about 8 inches high. I mowed (very short) again in the fall, with a bag on the mower. Lots of the QAL had set seed. Udoubtedly, I will have lots of QAL to work on this year.

I also had this extremely aggressive type of goldenrod that hopefully I got rid of, too. The round up did a number on it. April

if QAL is a biennial primarily and u had a lot of it flowering the first year after prep work, u see my problem?

and now u say u have a goldenrod coming up only 2 years after prep work.

i would postulate on a reason for ur situation this way;
rototilling did a total soil distruption and chopped up agressive perennials and others roots and stems and rhizomes, etc into a thick biological soup. u then proceded to kill off annuals and perennials with ur apps of round up thruout the growing season. but what may also have happened is that u mix'ed it up too strong and only topkilled some of the stronger and harder to kill longer lived plants vs easily killing shorter to live annuals (and their offspring cuz their annuals) that were easily rounded up. there is also the simple fact that one season of roundup sometimes just plainly doesnt do the trick on many spp. what remains is QAL and other 'stronger' plants. and this is where my original question comes up about what else is lurking there...

as to ur comment before about taking out the goldenrod with round up. how and when did u go about doing that? because, not only have u killed that little area of goldenrod (if ur lucky, u killed it...) but u prolly also killed many of the little seedings that are trying to eek out a living under the cover of larger plants; ie ur seeded prairie seedlings.

my suggestion is to make sure that u spray the goldenrod whilst in flower with a very fine 1.5% solution on a calm morning after the freeze date or just as the goldenrod is in full hight of flowering. after freeze date is less agressive and full flowering is a more agressive treatment. and as one moves up the agressive scale, one also moves up the side effects of the treatment. thats why i say that one has to pick their battles wisely, because many times the treatment is causing more harm than the surface disease.

i would also re-seed these treated areas with the faster growing pioneering plants. because chances are better than not that all that is gonna come up after a spot treatment of a complete killer like round up is more bad stuff because u have already seen what is already in the soil and u have just sprayed away ur 2year old seedlings. round up kills green but not seeds, roots and other would be nastyies. nature abhors a vacuum and sumthing is gonna grow there...if u have 30 years of weed seeds and roots and others vs 1 seeding of prairie that takes 10+yrs to get moving...

froggy

Froggy,

I put round-up on the goldenrod all season long, before I even had the idea of roto-tilling the following spring. The golden-rod and QAL were very well established before I even conceived of the idea of a small prairie...at least 7 years before, which is when DH bought the house. Doesn't matter if QAL is biennial or not...if you've got well established parent plants, you will have new seedlings every year.

I used the round up in exactly the dilution the label recommended. And I haven't used round up since I seeded my prairie. I'm not that dumb, LOL! April

i would be more aggressive in my effort against the goldenrod than i would the queen ann's lace.

unfortunately tilling is not effective for goldenrod as it can double the number of plants, by splitting the rhizomatous root structure.

my brother has had some success controlling the goldenrod by mowing it off during the peak growing season (like in July) to keep it from seeding and then hitting it again with an early fall burn. those two in combination does set it back it bit ...

Thanks for all the great help, peeps! I hit the goldenrod with the round up when it was 1 foot high, what was left when it was 3 feet high, and anything left when it bloomed. I chopped off the flowers and painted it on the cut stalks with the round up. I used the dilution recommended on the label, and within the correct ambient temperature range, as it was indicated to me(by someone with an applicator's license)that applying round-up when it's over 80 degrees or under 50 degrees is a waste of time, money and chemical. Most of it looked pretty dang dead to me.

Then, the following spring, I roto-tilled, used round-up 3 times @ approx. 5 week intervals after that, which took me to about mid-September. In late November, I cleaned up all the dead stuff, planted the prairie seed and raked it in. I haven't used chemicals, or done hand pulling since the prairie seed was planted. I know what this goldenrod looks like, and it's only in one corner of the little prairie, so if it shows up again, I will just keep cutting it back and daubing the cut end of the stalk with round-up. Same with the QAL. I probably wasn't making myself very clear. Sorry! April

Thanks for all the great help, peeps! I hit the goldenrod with the round up when it was 1 foot high, what was left when it was 3 feet high, and anything left when it bloomed. I chopped off the flowers and painted it on the cut stalks with the round up. I used the dilution recommended on the label, and within the correct ambient temperature range, as it was indicated to me(by someone with an applicator's license)that applying round-up when it's over 80 degrees or under 50 degrees is a waste of time, money and chemical. Most of it looked pretty dang dead to me.

Then, the following spring, I roto-tilled, used round-up 3 times @ approx. 5 week intervals after that, which took me to about mid-September. In late November, I cleaned up all the dead stuff, planted the prairie seed and raked it in. I haven't used chemicals, or done hand pulling since the prairie seed was planted. I know what this goldenrod looks like, and it's only in one corner of the little prairie, so if it shows up again, I will just keep cutting it back and daubing the cut end of the stalk with round-up. Same with the QAL. I probably wasn't making myself very clear. Sorry! April