Author Topic: Dead bearss lime tree  (Read 2279 times)

tve

  • Member
  • ***
  • Posts: 121
    • Santa Barbara, CA
    • View Profile
    • Intro post
Dead bearss lime tree
« on: May 30, 2020, 02:59:59 PM »
This winter our Bearss lime tree, planted in 2002, started to look sad. Overall thinning of foliage, twigs drying out. An algerian clementine that is about 12' away showed similar symptoms a few years ago and looked like it was going to die but after 2 almost-dead years it recovered and provided us with fruit for 5 months this spring. About a month ago the bearss lime went from looking sad to dead in maybe a week. I noticed that the bark peels off easily. I don't see any oozing. Location is Santa Barbara, sandy soil slope. I've gone through citrus disease keys and can't really nail it. Any thoughts about what the most likely causes are given soil & location?


This phot was taken after I removed the easy-to-peel bark, which is shown a couple of images down.






spaugh

  • Hero Member
  • *****
  • Posts: 5126
    • San Diego County California
    • View Profile
Re: Dead bearss lime tree
« Reply #1 on: May 30, 2020, 03:10:11 PM »
Not sure it has anything to do with the death of the tree but it looks like rabbits or somwthing may have been chewing the bark around the ground level.
Brad Spaugh

SeaWalnut

  • Hero Member
  • *****
  • Posts: 1397
    • Romania zone 6
    • View Profile
Re: Dead bearss lime tree
« Reply #2 on: May 30, 2020, 09:53:12 PM »
The simptoms are that of Armillaria fungi.
Look into Armillaria root rot.

tve

  • Member
  • ***
  • Posts: 121
    • Santa Barbara, CA
    • View Profile
    • Intro post
Re: Dead bearss lime tree
« Reply #3 on: May 30, 2020, 11:27:46 PM »
The simptoms are that of Armillaria fungi.
Look into Armillaria root rot.
Sort-of, except that I have not seen mycelia under the bark and there also were no mushrooms under the tree in the winter. Oak root fungus definitely is around, so it's plausible.

Millet

  • Moderator
  • Hero Member
  • *****
  • Posts: 4798
    • Colorado
    • View Profile
Re: Dead bearss lime tree
« Reply #4 on: May 31, 2020, 10:57:54 AM »
Doesn't look like mellea to me.  but it does look to be either gummosis phytophthora sp disease on the trunk of the tree, or foot rot caused by phytophthora nicotianae. 

SeaWalnut

  • Hero Member
  • *****
  • Posts: 1397
    • Romania zone 6
    • View Profile
Re: Dead bearss lime tree
« Reply #5 on: May 31, 2020, 05:22:36 PM »
On a positive side,it started to grow new shots that look healthy so i wouldnt consider this tree dead iet.
Hope it recovers and also no black shoe sting like formations to be Armillaria.

kumin

  • Hero Member
  • *****
  • Posts: 709
    • USA PA 6b
    • View Profile
Re: Dead bearss lime tree
« Reply #6 on: May 31, 2020, 05:55:27 PM »
The scion appears totally dead, while the roots don't. I'm curious what causes this condition. I may not be correct, but would expect a disease attacking the root system first, to kill the root system outright.

Oolie

  • Hero Member
  • *****
  • Posts: 1282
    • San Diego
    • View Profile
Re: Dead bearss lime tree
« Reply #7 on: June 01, 2020, 01:23:21 AM »
The scion appears totally dead, while the roots don't. I'm curious what causes this condition. I may not be correct, but would expect a disease attacking the root system first, to kill the root system outright.

Look again, I think those are lime leaves.

tve

  • Member
  • ***
  • Posts: 121
    • Santa Barbara, CA
    • View Profile
    • Intro post
Re: Dead bearss lime tree
« Reply #8 on: June 08, 2020, 03:38:29 AM »
I do not know what the rootstock is, are you sure these cannot be rootstock leaves?

In reading about Bearss lime on UCR CitrusVariety I came across this: "To date, all Persian lime trees are known to carry wood pocket, which can cause serious deterioration of the trees." Scientific name: lignocortosis. Searching around a bit more: "Characteristics of this disease are breakage or small defects on the bark of the tree. When you lift the bark, you can see that the bark underneath has become discolored. The tree can, unfortunately, die from this disease."

More: "The first evidence of the disease is generally a chimeralike variegation or blotching of the leaves (fig. 27A) . Frequently there is considerable chimeral striping of the fruit, especially of limes. The leaf color varies from only a slight loss of green to greenish-yellow to nearly pure yellow with diverse outlines. The disease apparently is a chimeral disorder which is seed- and bud-perpetuated but which is not transmissible by grafting. A short, narrow, irregular break in the bark of the trunk or limb is the first symptom on those parts (fig. 27B). The wood underneath discolors in definite regions even before this bark symptom appears. This led to the name wood pocket or lignocortosis. Elongated areas of dead, fissured bark, 1 inch to several feet in length, form on one side of the branches or on portions of the trunk. Wood underneath becomes irregularly discolored and darkly dotted in longitudinal view. Branches lose their leaves and die back gradually, or the leaves wilt suddenly as the branches die." From "VIRUS AND VIRUSLIKE DISEASE OF CITRUS" by KLOTZ, CALAVAN, WEATHERS.



The only thing that doesn't match is that I didn't see blotching of the leaves beforehand.

My biggest question is what I can plant in that spot... If it's really wood pocket I can put a new Bearss lime tree in (CCPP doesn't seem to have any other tahitian lime). If it's a root pathogen I'm in trouble...

citrange

  • Member
  • ***
  • Posts: 146
    • UK - 15 miles west of London
    • View Profile
    • Home Citrus growers
Re: Dead bearss lime tree
« Reply #9 on: June 10, 2020, 12:28:33 PM »
To me this looks like the common phytophthora which is a soil-borne pathogen. The graft line of your tree is only just above ground level which allows water splashes with soil and debris to reach the top variety. In addition, the rootstock and the Bears Lime don't seem ideally compatible so, clearly after many years, the knobbly graft union shape allows such splashes to lodge above the graft and cause problems. One of the purposes of using a grafted tree is to ensure the top variety is raised well above ground level. Either your tree was planted too deeply or the surrounding level has built up over time.

tve

  • Member
  • ***
  • Posts: 121
    • Santa Barbara, CA
    • View Profile
    • Intro post
Re: Dead bearss lime tree
« Reply #10 on: June 10, 2020, 03:02:01 PM »
To me this looks like the common phytophthora which is a soil-borne pathogen.
Can you tell me what makes it look like phytophthora to you? I'm trying to learn...
Quote
The graft line of your tree is only just above ground level which allows water splashes with soil and debris to reach the top variety. In addition, the rootstock and the Bears Lime don't seem ideally compatible so, clearly after many years, the knobbly graft union shape allows such splashes to lodge above the graft and cause problems. One of the purposes of using a grafted tree is to ensure the top variety is raised well above ground level. Either your tree was planted too deeply or the surrounding level has built up over time.
Yup.

Millet

  • Moderator
  • Hero Member
  • *****
  • Posts: 4798
    • Colorado
    • View Profile
Re: Dead bearss lime tree
« Reply #11 on: June 10, 2020, 03:15:09 PM »
I agree with citrange, I wrote the same thing in my post above.  It certainly looks like phytopthora

tve

  • Member
  • ***
  • Posts: 121
    • Santa Barbara, CA
    • View Profile
    • Intro post
Re: Dead bearss lime tree
« Reply #12 on: June 10, 2020, 04:10:27 PM »
It certainly looks like phytopthora
What are the things you look for? I'm trying to learn...

citrange

  • Member
  • ***
  • Posts: 146
    • UK - 15 miles west of London
    • View Profile
    • Home Citrus growers
Re: Dead bearss lime tree
« Reply #13 on: June 18, 2020, 01:59:42 AM »
Put "citrus phytophthora" into a search website and look at the images. Many will show cracked, peeling and dead wood near the base of the tree - very similar to your photo.
Without laboratory testing and culture of the pathogen it is impossible to say what exactly is the cause. No doubt there are other possibilities, but phytophthora on citrus is very common and is therefore the most likely in this case.