Desert Broomrape

[Gee.S]

These lovely little flower stalks have appeared on my property, and I have never seen them before. Stems are quite stout. Any ideas?

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[Gee.S]

I believe I have this sorted out. It appears to be something really interesting, Desert Broomrape, Orobanche cooperi. Now the question is, do I try to destroy it, or let it play out? It does seem to be parasitizing two of my Agaves. Coincidentally, I have a mistletoe-infested Palo Verde tree a few feet away.

[Spination]

It's quite nice looking, at least right now...

[Gee.S]

I'm just guessing that the person responsible for its common name, didn't like it very much.

[Spination]

Yup, that pretty much settles it...gotta go.
Uh, I mean...
" As a parasite taking its nutrients from a host plant..."

[Melt in the Sun]

It is quite pretty. Not sure I would let it stick around though...

[Gee.S]

Not sure how to rid myself of it without a backhoe. I'm thinking of digging up and tossing the two Agaves it seems to be parasitizing, That should at least slow it down, and hopefully kill it by depriving it of its nutrient source, but there is a tree in the area, and if it can draw resources from the tree, there's really no point. What to do, what to do...

[Peterthecactusguy]

The one I had looked different.

[Gee.S]

I've checked my field guide and online images; it seems a perfect match.

[MsWhipplei]

This is about a related species, repeat, related, not the same species, but still

2 Control stratagies
Many management strategies have been tried against Orobanche ramosa and other broomrapes, but few of them have proved reliable and these are only economical in high value agriculture.

The strength of branched broomrape lies in its ability to form a bank of seeds in the soil. A management or eradication program must aim at reducing this seed bank, while minimising the production of new seeds and their dispersal to new sites. Quarantine is therefore an essential element in control or eradication programs.

A simulation model (Kebreab & Murdoch, 2001) predicted that sustainable control of Orobanche spp. requires permanently a permanent reduction of the seed bank to below 2000 seeds per square metre. Cultural control techniques, applied individually in their model, needed to be highly effective to achieve this reduction; integrated control using several techniques including those aimed at reducing seed recruitment was therefore recommended.

In-crop control of Orobanche also requires an integrated strategy. Linke & Saxena (1991b) recommended a combination of solarisation, herbicides and hand weeding with careful choice of cultivars and sowing times to manage Orobanche in legume crops; none of these methods gave complete control when used separately.

From page 5 of this thrilling report.

Kill it with fire...!

[Gee.S]

Thanks, good stuff!

[Gee.S]

OK I pulled the A. vilmoriniana variegate up, and found nothing unusual, though I had removed a massive amount of broomrape plant/root several days ago with the flower stalks. I'll leave the plant outside for a week or so, then pot it up to see if that was enough to free it of the parasite. I still have a large A. guadalajarana to dig up, though it is not nearly as infested as the other.

BTW, now that we know what to look for, we're seeing plenty of broomrape blooms on our habitat excursions.

[Gee.S]

We found another kind of broomrape, Clustered Broomrape (Orobanche fasciculata), out in habitat today.

[Shmuel]

There are Orobanche species in Israel and some quite attractive. They can be very nasty on cultivated crops, but I don't know how bad they are in a xerophhytic garden.

Wikipedia had some good info on the Egyptian broomrape:
http://en.wikipedia.org/wiki/Orobanche_aegyptiaca" onclick="window.open(this.href);return false;

I recommend you check it out as it has some really good basic lifecycle info and control suggestions.

Good luck with it!

Shmuel

[Gee.S]

I was checking the side of my house the other day, and was surprised to find two very large depressions. It appears that Javalinas discovered broomrape blooms and found them completely delicious! So it might very well be that the parasitic plants are now gone from my property. Fingers crossed.

[Arizona Girl]

I first saw this species up Mount Lemmon going down the Oracle Ridge trail. It was the month of August I believe. Turns out there are herbarium records for this area, but the plant seems to occur at many different elevations. I'd love it if it popped up in my yard. I do have Hymenoclea (burro bush) in my yard which one reference said it was associated with. Not sure if they meant it was a host or not.

[mcvansoest]

I was checking the side of my house the other day, and was surprised to find two very large depressions. It appears that Javalinas discovered broomrape blooms and found them completely delicious! So it might very well be that the parasitic plants are now gone from my property. Fingers crossed.

It is not very often that Javelinas are mentioned in a positive sense when it comes to a garden forum...

[Gee.S]

I first saw this species up Mount Lemmon going down the Oracle Ridge trail. It was the month of August I believe. Turns out there are herbarium records for this area, but the plant seems to occur at many different elevations. I'd love it if it popped up in my yard. I do have Hymenoclea (burro bush) in my yard which one reference said it was associated with. Not sure if they meant it was a host or not.

It's all well and good until they pop up in the vicinity of an inexplicably sickly Agave. This is their bloom time now (Feb - Apr), they're very common along hiking trails and easy to spot while blooming.

[Gee.S]

I've only recently become aware that the common wildflower Indian Paint is also parasitic and considered a Broomrape -- different genus but same family. Here is a very rare yellow bracted example of Castilleja angustifolia (aka C. chromosa) found in habitat.