Scarring

[Micromegas]

Hey, can anyone help me out regarding the cause of this scarring on my cacti? Frost bite from early spring (growing while frosty?), snails, excessive sun? Mostly predominant on the pachanois, main columns and pups. Cacti are grown in heavy soil in a very exposed area... sacrring seems to grow out at some point (judging by last years growth)... hopefully...

Also any indication why my plants are pupping so profusely - to such an extreme I sometimes wish they'd do it a bit less

Thanks,

Micro

[ajna]

hey micro, i guess it could be anything eating out the tip, but i have seen this kind of damage on pachs caused by some caterpillar that sets up home there, they cover the tip with a white web layer and mature inside eating the tip. the branch usually only continues to grow if the very centre is still intact. i'd keep an eye out for them and any other critters that hang about

[TheFriendlyPlanter]

Possibly frost, the pups start up because the growing tip has been damaged. A bit of frost damage can have a simmilar effect to pruning, i.e it can result in the growth of more shoots than were previously there, and can be seen as a good thing if you're an optimist (like some guy I once knew).

[tonic]

Definitely frost damage.

[Micromegas]

Thanks, frost was my main candidate due to the lack of any noticeable insect infestations... bit strange it is happening on some of the plants now in the middle of summer though, while others are out-growing it. I think perhaps with the number of pups, it slows the gorwth of the main column and gives it more of a chance to receive damage. I'll keep an eye on it...

[incognito]

id say caterpillar damage, they love chewing out the growing tips on young specimens.

in my experience, frost damage causes the tip to 'melt' it goes all gluggy and black, all kinda oozy, then it drys up and callouses of , if ur lucky not to lose the entire plant. did this happen at any stage? ie the whole 'melting' and 'oozing' after the frost?

otherwise id put my 5 buks on cat damge. just view the reaction ur acctyi have after frosts. though thats a pchanoi right? theyseem to be imune to heavy frosts from my experience and understanding. my pachs used to be fine after the heaviest of black frosts, though my lageniformis vars used to suffer terribly aside from eileen, who also seems to be imune.

edit- btw u have to have a keen eye to spot cats on ur cacti, normally early morning, lateafternoon. duringthe daythey usually hide under the lip of the pot or somewhere else tricky. plus theycamo to the samecolor of thecacti. oh yeah and pupping profusely? is this the ones that have the damgeto the growing tip? thats a survival thing by the cacti i think. like if u want ur cacti to pup, damage the growing tip, i.e insert a large spine straight down the centre of it.

hopeive been sum help,

-jono

Edited November 17, 2007 by jono

[devance]

Grubs [beetle larva] only come out at night.

There are many people that think grubs only eat the roots.

Dusting some pyrethrin dust and watering will kill the nasty grubs.

Possibly a myth the snails can be taken can by putting a copper wire ribboncircle around the plant.

[Micromegas]

OK, well, intially thinking humbug to pests (since I never saw any in daylight) these posts however got me thinking, so when i got home about 11 tonight I went out to the garden with the torch...

and my oh my what a paradise for insects

The main candidate was a minute grey/white bug maybe .2 (smallest) to 2mm (largest) in size that was all over the top of most of the cacti that I looked at (in varying quantity, sometimes a few, sometimes quite a lot), some of these cacti have the scarring in the above photo and scarring on the tip, some don't. More don't than do, unfortunately.

(BTW, tip scarring doesn't seem to corellate to pup production with any consistency)

The second was a small brown millipede/caterpillar about 1cm, but over about 35 plants there were only two.

The third candidate for destruction was the earwig. About a fifth to a quarter of the plants had one to four earwigs on or near the top of the plant. They seemed to be sitting on the top - where the small bugs were - and, dare I say it, munching the top of the cacti!!! perhaps eating the smaller bugs...

Fourthly, many cacti had a resident spider...

So that was my unfortunate discovery does this halp narrow down the causes for the scarring? Incidentally last year's growth (during which time I was absent) is marked by a ring of scarring anout an 1 1/2 inch, followed by about 6 - 12 inches of healthy material, and now scarring again - is there a busy season for pests?

Overall the plants look plump and healthy, ready to grow...

I really appreciate the advice and any more will be gladly taken on board...

Thanks,

Micro

[Micromegas]

Here's a couple of examples of the old-growth ring of scarring... the majority of cacti that have been the ground for two growing seasons or more (this being the second for the majority of plants) have a ring like this for each year, to varying degrees of damage and thin-ness, and from the same time period...

Edited November 18, 2007 by Micromegas

[Micromegas]

*see above*

Edited November 18, 2007 by Micromegas

[The Dude]

If they still survive then this frost ring appearing each year is pretty cool as you can tell the age fairly easily that way.

[Micromegas]

I'd prefer unblemished plants of course, but it is interesting...

However frost seems not to be the issue after all... unless it was frost last year and a new problem this year. This morning I have found actual bites on the tips of 3 or four cacti, as in the photo attached... these apparently callous over and become a scar... I think

So any ideas what is going on? My thinking is earwigs, given the size of the bites and their presence last night... but the little white bugs could be doing damage as well...

But the interesting thing is, why would they have only a short period eating the tips of the plants, then letting them alone. Some plants that are scarred badly are starting to outgrow the problem; others scarred less now seem under attack, like some infuriating earwig rotation system...

But why the ring?

Is there an earwig or insect festival season? Is the beginning of summer banquet time, like chirtsmas holidays for nefarious bugs...

Any suggestions what to do? Be patient, or bite back?

Thanks in advance,

Micro

[mark80]

Bite back.

There going to wreck your plants I know from experince. They eat out the meristem and a lil aorund it but thats it. They can destroy a whole garden in a few nights (i lost 8 decent sized pedros to these guys - well not lots but they started pupping. although they are now used for grafting stock )

Just hit them with pyerthin spary or powder. Rose dust is preety good apart from the sulphur. So add a lilttle bt of lime with the first few waterings.

[incognito]

did u know how they got the tearm 'earwigs'?

ive heard that they used to be implemented in medieval torture techniques, where they were inserted into a victims ear, and they can only go forward and not backward!!!

[XipeTotec]

did u know how they got the tearm 'earwigs'?

ive heard that they used to be implemented in medieval torture techniques, where they were inserted into a victims ear, and they can only go forward and not backward!!!

i have heard a few reasons.... but I noticed one year... i was finding alot tucked in amongst my "ears" of corn, i decided that this must be where it came from.

[Micromegas]

Thanks again...

After some research turns out this pest is the European Earwig, whose diet is 60% carniverous but also likes to feed on the fresh growth of plants, vegetables etc. (i.e cacti tips are perfect). Incidentally there are about 60 species of native australian earwigs which are apparently beneficial for the garden, if present.

The term earwig seems to have come about due to a folk legend that the insect could crawl into the ear while a person is asleep and bore itself into the brain.

How delightful.

Control of earwigs ranges from spraying with insecticide (which I'd rather not do, partly because of the large number of plants needing protection) to laying bait/traps such as containers buried to the soil level containing vegetable oil, or carboard/soaked newspaper with oatmeal, to capture the eagwigs for future execution...

I've set up some traps to see how it goes.

Earwigs live for only one year, coming out of the ground in June/July and maturing in early spring after 70 days. This might explain why their are old rings indicative of past infestation are present... perhaps they diminish in the middle of summer due to the heat, wind and dryness (which my garden has in spades) and the plant can regenerate...

Finally, I wonder why the pedros in particular are the tasty morsel of choice?

[Micromegas]

Caught at 11:30 p.m... this morning only one plant had fresh bites, as opposed to 4 or 5 as usual. Little buggers were just sitting at the top chowing down... hard-core organic pest control...

Too stormy tonight for another assault...

[The Dude]

I wonder why the pedros in particular are the tasty morsel of choice?

Is there really any question? It seems pretty obvious

I've set up some traps to see how it goes.

You catch any in that? or only the ones you caught in the act. Little buggers eh! If i caught em in the act I'd chastise them hard. Killing them is bad for buddhist style reasons, on the other hand it promotes darwinist survival of the fittest by selecting a non-pedro eating population for survival.

trapped ones i'd spare but the ones munchin on pedros might need to die for the aformentioned reasons. Do you think they'd update the collective memory with the wrath of [to them] god, and modify their behaviour to appease god and .: survive. - I hope so.

Maybe they'll capture munchers of pedro by their own volition and sacrifice them to appease the almighty foot of death.

...rambling a bit, i guess im trying to think about a prevention instead of a nightly debugging.

[Micromegas]

You catch any in that? or only the ones you caught in the act. Little buggers eh! If i caught em in the act I'd chastise them hard. Killing them is bad for buddhist style reasons, on the other hand it promotes darwinist survival of the fittest by selecting a non-pedro eating population for survival.

I caught a few in the trap - they took swimming lessons too... but unsucessfully A few stumbled into a ice-cream container buried up to the surface with a few cms of vegetable oil (apparently they like that too)... but catching them is by far the most effective method...

Rain, wind and cold meant only a meagre offering tonight...

I thought for a while about the ethics of it; then what sort of lesson it contained for me, catching earwigs. I find it strangely exhillarating. Better than going to bed not having made an effort to protect the flock so to speak...

trapped ones i'd spare but the ones munchin on pedros might need to die for the aformentioned reasons. Do you think they'd update the collective memory with the wrath of [to them] god, and modify their behaviour to appease god and .: survive. - I hope so.

Maybe they'll capture munchers of pedro by their own volition and sacrifice them to appease the almighty foot of death.

...rambling a bit, i guess im trying to think about a prevention instead of a nightly debugging.

Yeah I like where you are coming from with this, maybe i'll select the biggest toughest ones and read them the gospel. But how can I proclaim that eating San Pedro is a sin, punishable by death?

Overall I get the impression they have a 'feasting season', seems that's what the rings indicate....

Micro

Edited November 21, 2007 by Micromegas