Wild Lettuce Crosses?

[Ferdzy]

Wild lettuce has been a relatively common weed in our back yard since we started up gardening here. There are at least 2 species that I am aware of. Which ones they are, exactly, I don't know. Looks like there are at least 4 relatively common wild lettuces around here, by which I mean latuca spp.

This spring I've been seeing a few plants that look like this pop up around the garden. So, questions: is this straight up wild lettuce of some kind? I suspect it is actually a cross between one of my domestic lettuces and wild lettuce, but who knows? (Somebody here, I hope). It tastes like bitter, bolting lettuce even though it is just getting started. On the other hand, it is way ahead of any domestic lettuce in the garden.

So, is this interesting? Or just another damn weed?

[reed]

Looks like and your description sounds like its a weed to me but I have strong dislike of bitter tasting lettuce. We have lots of similar looking plants, all that I've tried taste pretty nasty.

[William Schlegel]

In my garden I get crosses with Lactuca serriola which are observable readily because they have red marks from the domestic.

This individual in your photo could be a hybrid or it could be 100% Lactuca serriola. 

[Joseph Lofthouse]

The first photo shows what I think was an F1 hybrid between my wild lettuce and Romaine.

The second photo shows a pure wild plant (left), and domestic Simpson's black seeded (right), and what I think is an F1 hybrid in the middle.

The third photo is about an F3 or F4.

I select for winter hardiness, quick/early growth, and against spines and bitterness.

[Ferdzy]

Thanks, all!

William, I do think it is a cross. Looking at pictures of lactuca seriola, I'd say it is one of the two wild lettuces we have in the garden. However, it has always been quite serrated even when young. This plant looks different from what I have seen before. Smoother, thinner, and with more oval leaves. Quite tender. Just tastes nasty. But not really nastier than some of the bitter greens people (other than me and Reed) eat.

Joseph, it sounds like it has been worthwhile for you to continue to grow your wild lettuce crosses out. You are saying F3 or F4; are they selfed, or have they back-crossed with domestic lettuce, do you know?

The winter hardiness and quick and early growth are precisely what struck me. Nothing else is as far along, including lettuce that germinated last fall and overwintered.

[William Schlegel]

The F1 of Joseph's and Ferdzy's putative F1 both fit within my mental model of the range of variation I see within Lactuca serriola. For instance I saw a plant like that in a city 15 miles away a few days ago. It's early yet. Then over the next couple months I would expect that seedling to harden, get stronger spines and look like the wild species photo. Early wild seedlings and also shade grown plants will have that domestic look. Also in my garden some of the domestic strains when they do bolt will look more like the wild than at any other time. Lactuca serriola is already an ancestor of some common cultivars. The more domestic look corresponds somewhat to juveniles and domestication to a certain extent is the plant staying in juvenile growth stages longer. However when you have two plants under the same conditions and ages generally these characters are pretty solid for hybridization. There is also probably some gene flow back into the wild. I've also noted that in Southern California wild lettuce plants Lactuca serriola still are much less common and have more trichomes or hairs than here in Western Montana. I've never been to Ontario but it is far east from here. I would not be surprised to find differences there given what I found in California. In my garden I currently have a domestic lettuce plant volunteer in a seed scattered section about four inches across. It's got the red markings on the leaves and some other distinctly domestic characters. My lettuce patches tend to be volunteer patches a lot of the time. Which means germination can be erratic and plants not even aged. I got one hybrid looking plant last year and I've no idea if it was a descendent of prior hybrids or a new hybridization event. It seems like a interesting exercise in lettuce breeding to track some generations of segregation as Joseph has done- given the years of local adaptation populations of Lactuca serriola have undergone. I just haven't followed up in a precise way in my garden. The cultivars with red markings transfer that character to the hybrids in my garden which makes them easier to spot for me. I tend to weed my volunteer beds with full knowledge of species. Suspect I weed out green Lactuca serriola hybrid lettuce and green orach seedlings to some extent. The latter because of its resemblance to chenopodium album opposed to the more common red seedlings.

http://ontariowildflowers.com/main/group.php?id=95

Lactuca biennis and Lactuca Canadensis are both found in Ontario according to this page. Probably less likely to hybridize with domestic though I haven't researched it extensively.

[Garrett Schantz]

Lactuca virosa and L. serriola both grow wild in my area. The two can apparently hybridize as well.

So figuring out an exact parent could be difficult.

Recently I have been saving seed from the wild lettuces and planting them near domestic lettuce - closer plants increases the chance of hybridization.

Maybe the F2 will help you figure out if it's a hybrid.

Some species contain different sap colors, that might help a bit.

[Joseph Lofthouse]

I estimate that lettuce, at my place is about 99.5% selfing. In damper climates, with higher insect populations, it might cross up to 6%.

I used to taste the lettuce to screen for bitterness. The bitter is poison, so I poisoned myself the first time I tasted about 300 lettuce plants. These days, I look at the sap color. I don't taste plants with thick milky sap. I can tell just by looking that they are nasty. And I spit these days after each taste. I don't have to taste plants with spines. I just cull them.

[Garrett Schantz]

Lactuca virosa resembles some of the L. sativa x serriola hybrids it seems like.
L. virosa has spines on the leaves like serriola does, it also has very smooth leaves. They can also get a sort of redness on the outer portion of the leaves.

First image I am posting is of a L. virosa plant that I found outside earlier. Didn't taste much bitterness, which is nice. Also not as many spines as usual... Suppose I will save seed.

Dunno what the next two images are. Pretty sure that they are a North American lettuce. They have a bad - bitter lettuce taste. They also have some small spines. Leaves aren't smooth like serriola / virosa - bit of a fuzz there.

There were very large/ tall plants in a wooded area by the house last year with similar leaves to these. I might inspect them more closely this year. I don't remember the leaves being exactly like this, even on the young plants though. Then again the plants that I took images of were all next to each other - so it could possibly be a hybrid. Though I doubt it. I would rather not have plants of that size appear in this particular area anyway.


https://extension.umass.edu/landscape/weeds/lactuca-biennis
There are some other images online of L. biennis that look different than the one showed on this website - last year's woodland plant looked like this.

Last image is just a leaf comparison.

[Joran Marechal]

Hi,
For the first photo it is a Lactuca sativa subsp. serriola.
Lactuca virosa have, at least during the rosette stage, characteristic large, perfectly round lobes.

For the following two photos it is indeed a North American species, I am French, I know European species, and I have never seen anything similar.

[Joran Marechal]

I have developed 4 lines of cultivated lettuce crossed with wild lettuce.
You can read the full article (and see the photographs, I didn't manage to post them) and buy seeds on my blog:
https://joransseeds.blogspot.com/2023/12/crossing.html?m=1]

__________________


Development of naturalizable lettuces by self-seeding by hybridization with its wild ancestor (Lactuca sativa subsp. serriola).


First published: December 3, 2023
Blog Joran's Seeds & Research : https://joransseeds.blogspot.com/

Joran Marechal
Joran's Seeds & Research
St Vincent de Durfort, Ardèche, France.

 

Abstract :
In an agroecological approach to permaculture or agroforestry, it is desirable to cultivate plants capable of naturalizing.
However, cultivated lettuce (Lactuca sativa subsp. sativa) has a very strong barrier to spontaneous propagation: its flower heads remain closed after the maturation of the seeds, the latter cannot therefore fly away as those of their wild ancestor would do (Lactuca sativa subsp. serriola).
If this characteristic resulting from human selection is essential in conventional cropping systems since it facilitates the harvest of seeds and avoids the uncontrolled propagation of plants, it is however less relevant in the context of an agroecological culture, based on the processes and ecosystem functions.
Based on a recessive character, this trait can be eliminated through hybridization with their wild ancestor: Lactuca sativa subsp. serriola.
 
Ultimately, this project aims to produce lines of naturalizable winter lettuce.
Developed for sowing in autumn, very easy to grow in open field conditions, they will not require irrigation or treatment; and will be able to naturalize thanks to the release of their seeds.
Harvested as "looseleaf" during the rosette stage, they can then:
- or be consumed as a "celtuce" type, once erected 30-40cm.
- or be left in place, as reproductive plants, to seed themselves according to the wind.
A dry matter level and bitterness slightly higher than standard lettuce cultivars will not be prohibitive since these characteristics contribute to the resistance of the plants.
The production of commercial quantities of seeds nevertheless remains possible by cultivating plants under cover. It will then be possible to harvest almost all of the seeds.
 
As part of this project, in 2022, four lines resulting from hybridizations between wild and cultivated lettuces were produced by Joran Marechal of Joran's Seeds & Research.
Four lettuce cultivars with open habit (non-headed) and reproducible seeds were used as maternal parents and wild lettuces (Lactuca sativa subsp. serriola) from the local flora of Ardèche, in the South of France, as paternal parents.
Use was made of the two botanical varieties of the serriola subspecies : var. serriola and var. integrifolia in different combinations.
 
The F1 hybrids were identified on the basis of morphological characteristics, and in particular on the presence of thorns on the midrib of the underside of the leaf as well as on the stem.
They combined the characteristics of both parental lines:
They had a rosette almost as full as that of their maternal parent.
And flowered earlier than their cultivated parent. During flowering the hybrids developed strong stems and abundant vegetation. Their habit was reminiscent of their wild relative with very branched stems that could reach 2.5m high.
Their seeds flew away, like those of wild lettuce.
From an organoleptic point of view, the F1 hybrids presented a strong bitter taste from the rosette stage. And the foliage, when crumpled, gave off a pungent odor.

[Max Holzapfel]

Hi everyone,

this year i´m setting out to grow some Lactuca perennis.
As far as i know it seems to be mostly a european species, so i don´t know if it´s growing in the US or elsewhere
I got 9 different accessions from the german Genebank IPK Gatersleben and want to check them out for their different traits.
I´m especially interested in it beeing perennial.

I´m wondering what your thoughts are on crossing Lactuca perennis with Lactuca sativa?
Do you think this is possible or do you know about any barriers?
I imagine it to be quite similar to Lactuca serriola.
Lactuca perennis flowers in May/June and shall be cross-pollinating, so i plan on overwintering a few L. sativa to have them flowering a bit earlier then Spring sown.

Was just checking out your fascinating Blog Joran. Interesting results so far

[Joran Marechal]

Hi Max Holzapfel,
L. perennis is a plant that seems to me to have good potential for consumption and domestication: the plants live for several years (I would say 3 years and more, for mine), they are resistant, naturalize easily, and above all the taste of the leaves is surprisingly mild (no bitterness)!

However, sorry to disappoint you, Lactuca perennnis is perfectly incompatible with L.sativa.
Lactuca perennnis is phylogenetically very distant from L.sativa: it has flowers that really look like those of chicories (Cichorium), but unlike the latter, their seeds fly away, like those of L.sativa.
Hence its belonging, I suppose, to the genus Lactuca.

 Yes, the unfettered seed lettuce project is progressing well, now two of the four F2 lines have been selected with the phenotype of the domestic parent: leaf morphotype, spineless, glossy and green foliage, but with unfettered seeds (a characteristic from L. sativa var. serriola).
I have updated the article (and greatly improved the blog)

I am providing a link to the article:
https://joransseedsresearch.blogspot.com/2023/12/crossing.html?m=1

[Max Holzapfel]

Hi Joran,

been now almost a year now, but i stumbled recently over the "integrata red" variety which seems to be a cross between L. sativa and L.serriola integrata. I was just wondering if you are working with this one as well or considered this as part of your project?  https://kokopelli-semences.com/en/p/integrata-red-lettuce

I´m now also in the second year of working with L.perennis and actually i really like it as a cutting lettuce.
I´m now focussing more on regrowth ability and different leaf colours and leaf shapes thats already a lot

Thanks for your answer