I think you can still plant them. Think about this: When Monarchs migrate they pass through many places where different Milkweeds are native. I think they will do okay on any Milkweed. I think the Monarchs you have to be carefull are the "White" Monarchs. Have you heard of that species?

I found this a few years ago, it might help
-B

Here is a link that might be useful: different milkweeds

The White Monarchs are predominantly found in Hawaii (and even there, they are rare)...and I doubt that feeding various Asclepias spp. will be the cause. Several years ago, I had Monarch larvae that were called 'Zebra' because genetically, they were unable to process the chemicals within the Milkweed that would allow them to have the three colours that Monarch larvae should have! So, they ended up only black and white and when they pupated, they were almost a blue colour. When they eclosed, however, they were normal Monarchs. Dr. Karen Oberhauser, from the U of Minnesota, was interested in the larvae, and I guess this is uncommon yet it does occur occasionally!

I feel that the most important thing is to provide the best food for the larvae. Period. If the larvae are fed well, then you have the highest odds of having healthy adults, barring any unforeseen circumstances such as parasitoids, bacterial or viral infections, and the like.

The White or Albino Monarchs are quite rare and I don't think that feeding a particular species of Milkweed is more likely to result in them. Of course, I could be wrong!

Wow! I just learned something new today. I would have bet all the plants in my butterfly garden that there was only one kind of monarch. Just goes to show you're never too old to learn. Butterflutter

This is a very interesting question! I'm just north of the OP, and would be planting everything "A." I could get my hands on, but wow, what a good question.
Watching this thread intensely!

Ah, the age old milkweed question...
Monarch watch has a lot of information based on studies conducted on this question. Ask people what their monarchs prefer and each will give you a different answer. What with over 100 different milkweed species it can vary a lot. However, there are some issues involved. Monarchs typically feed on about 20 plus species. They do have laying preferences. Once mama lays her eggs the babies are stuck on that plant unless some nice person brings them in and gives them an asclepias smorgasbord. So, mama looks for the best plants available. Sometimes it's just what is available. At our butterfly house we have four to five types of milkweed at a time. There are definate preferences at the house. They prefer the "tropical" milkweed (Asclepias curasavica) over most, then the swamp milkweed (Asclepias incarnata), then common (Asclepias syriaca). They hardly ever lay on the butterfly weed (Asclepias tuberosa). One study I read said that due to the moisture content of tuberosa, they don't grow as fast. They cannot absorb enough nitrogen. This makes them more vulnerable to predators. Common milkweed, syriaca, is good but the nature of the latex makes it deadly to first instar larvae. However, many people have used these plants well in their garden.

In terms of the toxicity content of the plants, they have the ability to sequester cardiac glycosides somewhat independent of the level in the plants. Some plants have higher levels, with curassavica having some of the highest. Before I got into raising butterflies, they used honeyvine in my yard, which has no toxic cardiac glycosides but it was the only thing available for them to lay on and has good nutritional value.

I think mother nature has made the nature of the Monarch way more variable then we ever could. So, use what works for you. The Monarch has. Everywhere it has migrated too, Austrailia, Hawaii, etc. it has survived on what was available. Well, I guess, everywhere there was something it could eat. I guess if it migrated to fifth avenue in midtown Manhattan it might starve unless it could survive on Starbucks.

Cheers,
Elisabeth

Brandy, that study was interesting, particularly the conclusion that A. curassavica produced the fastest growing and greatest number of Monarchs. The study was probably not as tightly controlled as it could be, though, since they "recorded numbers and percentages...out of 20 original eggs, and not the number of eggs that have hatched" and some of the eggs may not have been fertile. I would love to read more scientific data on this topic.

Elisabeth, it makes sense that Monarchs would have the ability to adapt to the food supply to some extent. I will provide a variety of species and leave it up to Momma to decide where she is going to lay eggs. Last year they laid eggs on all 4 species growing in the yard, A. tuberosa, incarnata, syriaca, and curassavica, and they seemed to use incarnata the most, but that is what I have most of. I collected some eggs and cat and had 19 eclose successfully. Who knows how many eclosed outside and what Milkweeds they used?

Looks like the question about the various Asclepias has been addressed fairly well. I will add however that with Monarch's on the move passing through different habitats and so encountering different species of Asclepias that a females urge to oviposit is so strong that she will use what she finds if she doesn't find her preferences. For example, the most commonly used Asclepias by D. plexippus from the northern Mojave to the riparian habitats of the northern Rockies is A. speciosa, although they will and do use several other Asclepias species as well when they encounter them. Same in Hawaii. While C. gigantea is the mostly commonly used larval food plant of Monarch's there, they also use at least A. curassavica and A. physocarpa in Hawaii as well.

The White Monarch thing...
"I think the Monarchs you have to be carefull are the "White" Monarchs. Have you heard of that species?" I have no clue what any of that is suppose to mean Danny or what it could be based on. They are not a species, but rather a phenotype (nivosus) that can rarely occur in other Danainae species as well, not just in D. plexippus.

While nivosus Monarch's are rare in continental North America Sherry, they certainly are not in at least a couple of specific locations around the Pacific Rim. Best known places where their numbers have been the highest is on some islands in Hawaii, and in India. But they also occur in South America, NZ, OZ, Indonesia and Eurasia. It's true their numbers in Hawaii are not as high as they were during the years that I reared and studied them there (1980's & 1990's), but they do still make up to 10% of local populations in some places in Hawaii. BTW, they are not albino's. What their larva eats has nothing to do with whether a D. plexxipus adult will be nominate (orange), or either of the white or brown morphs. That is controlled entirely by a resessive gene found in all Monarch's. Any of you that have studied genetic ratios will understand why the nivosus phenotype can continually resurface in Hawaii/India to maintain a breeding population of white morphs, and why the same doesn't accur elsewhere where they are so rarely if ever seen at present.

When I said to be carefull with the white Monarchs I meant to give it Milkweeds only native to its area since not a "ton" of info is available about the white Monarch. When I said "Have you heard of this species" I meant has anyone heard o the White Monarch.

A heck of a lot more is known about Monarch phenotypes than I think you realize. The Hawaiian colonies of D. plexippus (including the white and brown phenotypes) have been studied heavily for at least the last three to four decades that I know of personally, plus all the work done on the phenotypes of other Danaus species worldwide. As for larval food plants, the D. plexippus colonies all around the Pacific Rim use quite a few different genera/species of Asclepiadaceae, so obviously they will accept a fairly wide range of plants. Besides the thousands I paired/reared while in Hawaii on local larval food plants over the years, I also did Hawaiian livestock at home on A. speciosa and A. subverticillata several times. Neither of these milkweed species occur in Hawaii, but they were readily accepted by the Hawaiian females and larva.

You seem to want to set apart the white phenotypes from the other D. plexippus in a colony, so I am not convinced you understand that a phenotype is just a genetic variant within that colony. IOW, all of the D. plexippus in a given colony use the same LFP's whether they are orange or white or brown.

Larry,
I do understand what you are saying. Karen Oberhauser used the info I sent her on the larvae I had in an article about how genetics can have an effect on Monarchs and that even within the same group, some can have a mutation that, like human siblings, may cause differences to exist, hence, the lack in ability to utilize the cardenolides in the Asclepias. The ones I had were not 'White' Monarchs but just had a recessive gene...and were called 'Zebra' in the larval form. As I mentioned, the imagines all were 'normal' in colour. The pupae, however, were somewhat of a light blue (quite lovely!). Too bad I didn't take pictures of the pupae...I do have pics of the larvae (which I'd have to sort through to find and show everyone) but I can give you guys the link to the article, if you are interested.

Here is a link that might be useful: Article from MLMP 2006 Newsletter re 'zebra' larvae

Pardon me, but I thought the statement made by Las Palitas wasn't that monarchs wouldn't eat all different types of milkweeds (which they obviously will),but that milkweeds specific to their migration path had alkaloids that worked specifically on the predators in their flight path.

Obviously, as they migrate they eat many different types of milkweed. However, a butterfly in the east is never going to (naturally) eat a ca milkweed, and vice versa.

I'm not saying this statement about protective chemicals and predators is true, but that's what I understood when I read the info on their website. It's _not_ (as I understand what they are saying) about whether the butterflies will eat all kinds of milkweed or not, nor is it about whether you can do so in captivity and what sort of success rate you'll have (like in the study linked to above), but more about whether it benefits them in the end or not against their natural predators local to their migratory path.

Here's the excerpt from their website--
"The alkaloids associated with this plant give the butterflies that feed on it protection. Alkaloids from the wrong milkweed(South American, Mexican, etc.) can expose the butterflies to predation. If the monarch or other butterfly has not evolved with the milkweed they have no tolerance for the particular alkaloid of the species. The California flyway runs from Baja to Canada, it does not include Mexico proper nor Central America. If you live in Chicago you can plant Mexican species (Asclepias mexicana) or Asclepias tuberosa, don't plant our species."

SteveB, that is the website I happened to be reading - because I received seeds for A. eriocarpa in a trade, which is native only to the state of California. Growing non-native plants concerns me in general because they can become invasive, but also because the insects and animals native to the northeast US have an inter-dependent relationship with the plants native to this region.

In this case, IF it germinates and grows okay, hopefully this California species will not be harmful to the Monarchs that breed in this area. (Although I plan to grow at least a dozen species native to the Northeast US.) Can the alkaloids be SO different that Monarchs who never fly through California can't use them at all?

I do not think so. I am growing a ton of different Milkweed varieties not native to my area.

Frankly, I do not, in my humble opinion, feel that the information that is posted on their website is completely accurate.

I think that if you read information from the scientists who study these butterflies, you will find that they are not going to share the same beliefs as printed on this particular nursery's website.

I've found misinformation shared on this nursery's website in other areas as well, yet I keep in mind that this is a nursery and their main function is plant sales. They definitely have a vested interest in what they share on-line because they are trying to sell their plants.

True, Asclepias spp. contain varying quantities of cardenolides but to state that a butterfly that has not grown up with a particular plant will have zero tolerance for a particular species? What? Doesn't this sound a bit odd? Maybe I'm missing something here.

Agree with you CalSherry. The statements are so far fetched that I could shoot a lot of holes in them just based on common sense and logic. But I could also back it up from the very extensive breeding I did and the thoughts of the crowd of professionals I used to run with.

Also, the school students linked to above get a star for effort on their school project, but anyone with any real world experience in genetics knows any hypothethes and conclusions that they drew came from such a miniscule sampling that they do not yeild any valid usable data at all. Even my findings from rearing thousands of individuals are far from etched in stone.

I've seen that reference at Las Pilitas, it's absurd!
I think their motivation in posting it is probably genuine, well intentioned, but likely "grow native" mentality taken too far.

I'm all for growing native, and avoiding aggressive non-natives -- but it gets ridiculous when you encounter gardeners who won't entertain talk of non-native plants or entertain a trade for the sole reason of nativity.

I know that different species of milkweed have different levels and combinations of poisons found in milkweeds.
Particularly the Monarch species with it's extreme migratory patterns, lay eggs on all species of Asclepias genus North America, and many other species from other genera of milkweeds -- including species not native to this part of the world. Successfully, I might add.
Plus the presence of Monarchs in northern South America -- uh, completely different milkweed species.

Naturally occurring and even imported dogbanes (like a Mandevilla) that confuse female egg laying Monarchs and other Danaus genus, or Danaidae family at large, to lay on their foliage that the caterpillar can't survive on are 1000% more threatening than a mature butterfly being eaten by a bird.

I've seen studies of egg lays on controlled species, and although they do give insight, I highly doubt that these studies can be applied to the real world in any direct way. I grow a variety of Asclepias species, and a few other milkweeds, and I've observed plant species that are thought to be preferential, to be completely eaten to the bare stems one year, and completely ignored the next. I suspect that maturity of the plant has a lot more to do with attracting eggs than does the species. I've even noticed that where I put plants in the yard has a small influence on attracting eggs laid to a species.

I did see a study once where they found a species of milkweed beetle was not capable of long term survival on a species milkweed from a different region of the country. The studies conclusion suggested it could be due to the difference in the poison levels or possibly the difference in the growth habits. In any case, the beetles don't migrate on the scale the Monarchs do, or even like the Queen or Soldier butterflies roam.