whats wrong with my agave ??

[vapester]

i pulled this, what i assume to be agave tequilana from a large colony out in Santa Barbara a few months back, i figured it would be like most agaves and be fine out of the soil for awhile. Well after a day or 2 it started showing this damage....so i get it home and put it in the ground, and it seems the new growth is still dying off rather quickly. Is this normal ? Is it diseased ? Here are some pics, any help is appreciated.

[Allen Repashy]

It appears the center growth looks ok to me but I could be wrong. One thing I can tell you is that you are going to be in big trouble if that plant does survive. It looks like you planted it about a foot from a wall or fence... You need to plant that thing FIVE FEET or more from anything. Just the heart of that thing without any leaves will be on the other side of the fence in a couple years

[vapester]

yeah i know it, you'r def right about that, i really wanted something tall to fill in that spot, and i've seen agave tequilana trimmed so leaves are more upright facing, still its prob too close to the fence....it is agave tequilana though right ? Guess i'll diggit up when i get back in town next weekend.

[agavemonger]

Hi, John...

This type of tissue collapse damage appears to be sun-burn related. I've noticed that when we've moved our Agaves around at the nursery on hot days, that sometimes we can get this type of destructive damage (but usually more extensive) . The side of the plant that got damaged was most likely on the shady side of the plant before it was moved. You will notice that generally, the damage is oriented to the 3 O'clock afternoon sun (usually the hottest part of the day).

A little trick I've learned to avoid these unsightly scars is to mark your pots or plants with a grease pencil as to which way is pointing south (or any direction, for that matter). Then when you move the plant, be sure to re-orient it in the same direction. With careful adherence to this technique, you should be able to avoid most of this type of damage! This works with other plants also, like cycads and Aloes, which can also get horribly burned.

Not to worry, though; as alarming as this appears, your plant will most certainly come out of it just fine!

The monger

[vapester]

well thanks for clearing that up for me, i needed someone to tell me to move it before it got to established there, i have questioned it myself. Thanks for the tip on sunburn and marking my pots as well, it will definitely simplify things. I always try and orient them the same when moving them but it will take the guesswork out. I passed the house again today that has 2 agave tequilana in front that are very trimmed with only semi upright spears and it does look nice, different anyway. But yeah the heart of those things are huge, i don't have a real ideal place for an agave tequilana, but i have a better one in mind then where it's at now.

[Boo Hollow]

Looking at the pattern on the leaf surface would be in my humble opinion, more aligned with insect damage vs. sunburn. The nonuniformity of the area is not typical with sunburn in my experience. Sunburn/sunscald typically will cause the perimeter tissues, those on the outer edges and tips, to discolor and collapse and then the surrounding tissues would start discoloration prior to collapse when exposed to sun after being shaded. Cuticle thickening at the outer edges and tips develops later in the growth cycle (if at all) and upon rapid exposure to sun, the cytoplasm collapses and the cell walls cave in resulting in the sunken appearance. Also, there is no contiguous discoloration or transition zone from the black areas to the adjacent normally colored leaf. The pattern also looks like it was the result of rasping down to the fibers, which is another example of slug or snail feeding or if a fungal causal agent such as Colletotrichum which we know as Antrhacnose. The patterns on the leaves do closely resemble this infection and if the plant was moved from a warm dry condition to a warm wet condition, this can happen quite rapidly is the spores were already on the plant. Was the plant near any Sycamore or trees of the Platanus genus? Rapid sunburn usually causes bleaching then necrotic tissuse becoming blackened based on secondary fungal/viral infections such as seen in Fire Blight. The recent heatwave here, where we have been seeing highs no greater than 75F then a sudden 107F over a 2-day period, bleached out quite a few plants to a pale yellow - white color and no blackened tissue was observed. However, on plants that have been damaged by slugs or snails and then exposed to the warm wet conditions, we have frequently observed fungal infections that create the blackened surfaces. Just my opinion.

[vapester]

well thats an interesting take as well, thing is when i yanked the plant out the ground initially it looked fine, well i thought it would remain that way for a bit as most agaves do, but it started showing that damage right away as it sat in the cool trunk of my car a couple days till i got it home. Then i planted it and the damage continued. Well yesterday i yanked it back out to transfer it and it had healthy new root formations, but the old 5 inch sucker was rotting off, so i snipped it off. I don't know where to really put it now, guess i'll pot it for a bit.

What i'd really like to know is this.......this plant looks green to me. Are all Agave Tequilanas blue-ish...at least eventually. Is this a less desirable color of it ? I suppose this is not the Weber Blue version right ?

[agavemonger]

Could it be that perhaps we are talking about Agave angustifolia here?

Do snails eat Calcium oxalate?

The monger

[Matt Maggio]

I agree that the damage doesn't equate with sunburn. Soon as I read that the plant was left in the trunk of a car for a couple days, a red flag went up. Here's the old thread on "Agave Edema" where myself and some others try to explain this physiological disorder.

Agave edema

[Boo Hollow]

Originally Posted by agavemonger

Could it be that perhaps we are talking about Agave angustifolia here?

Do snails eat Calcium oxalate?

The monger

Dear Mr. Monger - To answer your question briefly, Yes. To elaborate, look at the devastation that these molluscan beasts do to clover plants, or as in the Redwood Sorrel (Oxalis oregana) zones, entire beds of these plants under the shaded redwood canopies. We have nice patches of Redwood Sorrel growing in our fern garden and also in pots and the slugs and snails will munch them down to nubs in a heatbeat. The concentration of calcium oxalate is higher in oxalis than in agave, so anyone whom has grown agave will attest, snails and slugs will dine and dine. Iron phosphide, that is another story.