Re: Apple-Crop: Fireblight on Ernst Bosch
Hi! we tried to restart trees by leaving a few nodes above the graft, but failed miserably. The darn trees never re-sprouted. We had much better success pruning out the diseased portions. We also found sterilizing shears was a waste of time. The article can be found at: Toussaint, V., and Philion, V. 2007. NATURAL EPIDEMIC OF FIRE BLIGHT IN A NEWLY PLANTED ORCHARD AND EFFECT OF PRUNING ON DISEASE DEVELOPMENT. In XI International Workshop on Fire Blight 793, ISHS, p. 313-320. Vincent On 18-Jun-2009, at 2:17 PM, Mark Longstroth wrote: Good Job Allen. I discussed that type of program Monday with a grower. Other sad fireblight tales. I had a grower who planted RubiJon this spring, which bloomed after normal and now have blossom blight. I suggested cutting back to 2 or 3 nodes above the graft union in an effort to save the rootstock (M26) on any tree that showed any symptoms. He also had a block of Idared on G30 which got fireblight in the fall (leaf hoppers?). He noticed 30 dead trees out of 150 this winter when he pruned but about half the planting has or is collapsing now and he will remove them all. - Mark Longstroth SW Michigan District Fruit Educator Van Buren County MSU Extension Email - longs...@msu.edu http://web1.msue.msu.edu/vanburen/disthort.htm - -Original Message- From: apple-crop@virtualorchard.net [mailto:apple-crop@virtualorchard.net ]On Behalf Of Allen Teach - Sunrise Orchard Sent: Thursday, June 18, 2009 1:01 PM To: Apple-Crop Subject: Re: Apple-Crop: Fireblight on Ernst Bosch Gentlemen: I certainly agree with Mark to get rid of the culprit tree yesterday. However, let me relay an experience we had last year. On a five acre block of 3rd leaf Honeycrisp on B9 and CG 16 (tall spindle) we had some blossom blight on very late rat tail bloom and began seeing sporadic shoot blight in late June. I immediately made ugly stub cuts on the affected branches, fired up the sprayer and applied Apogee to the entire block. I continued to patrol the block and reapplied the Apogee about 3 weeks later. this is totally unscientific but we were able to avoid a disaster. Granted Honeycrisp/B9-CG 16 is not extremely susceptible but we had the trees set up with water and fertilizer to grow vigorously. Allen Teach Sunrise Orchards Inc. Gays Mills, WI P.S. Let's all dodge the severe weather the next couple of days! - Original Message - From: Axel Kratel To: Apple-Crop Sent: Thursday, June 18, 2009 11:18 AM Subject: Re: Apple-Crop: Fireblight on Ernst Bosch Mark, that sounds like good advice. Basically, I cut once, that didn't help. I cut again. if it comes back again I will yank out the tree. I do have a question for the group: When fireblight die back shows up as a result of flowers getting rained on, which of these two reasons would cause it: 1) Fireblight is systemic in the tree 2) Fireblight was brought to the tree from an outside vector. Thanks. From: Mark Longstroth longs...@msu.edu To: Apple-Crop apple-crop@virtualorchard.net Sent: Thursday, June 18, 2009 7:36:12 AM Subject: RE: Apple-Crop: Fireblight on Ernst Bosch Axel, If I had a 4 year old tree in an orchard of 200 trees with fireblight that bad, I would yank it out of the ground today! In my experience, 4 year old trees with that bad an infection don't survive. It sounds like the bacteria is running faster than you can cut and in my experience it will run very fast in wood back through three year old wood and in a 4 year old tree it is just a short jump to the rootstock. MM111 is rated as moderately resistant and I doubt it will survive with an infected susceptible scion such as you describe. If you inject strep into the tree you might save it or find out that you have a resistant strain in your orchard. Do you really want a source of fireblight in your orchard while you try to save one tree? What are you going to do if you have a storm which spreads the infection to other trees? Get rid of it now while the infection is only in one tree. It is much easier to manage fireblight if you do not have a source in the orchard. I saw fireblight literally destroy hundreds of acres of apple trees in 2000 here in SW Michigan. The industry still has not recovered from that epidemic. - Mark Longstroth SW Michigan District Fruit Educator Van Buren County MSU Extension Email - longs...@msu.edu http://web1.msue.msu.edu/vanburen/disthort.htm - -Original Message- From: apple-crop@virtualorchard.net [mailto:apple-crop@virtualorchard.net ]On Behalf Of Axel Kratel Sent: Wednesday, June 17, 2009 12:19 AM To: Apple-Crop Subject: Apple-Crop: Fireblight on Ernst Bosch Dear all, I have an Ernst Bosch apple tree on MM111 that has developed a pretty bad case of
Re: Apple-Crop: Fireblight on Ernst Bosch
I finally figured out what is going on. Because of the earlier infection, the tree bark is covered with fireblight bacteria even though the wood is not infected. A cut with pruning sheers inevitably re-infects the tree at the cut location. A real important step in controlling fireblight is to fully sterilize the tree, or sterilize the cut area before pruning, sterilize after pruning, and seal the cut so that the fireblight bacteria present on the bark on surrounding branches can't infect the tree. From: Vincent Philion vincent.phil...@irda.qc.ca To: Apple-Crop apple-crop@virtualorchard.net Sent: Monday, June 22, 2009 1:20:12 PM Subject: Re: Apple-Crop: Fireblight on Ernst Bosch Hi! we tried to restart trees by leaving a few nodes above the graft, but failed miserably. The darn trees never re-sprouted. We had much better success pruning out the diseased portions. We also found sterilizing shears was a waste of time. The article can be found at: Toussaint, V., and Philion, V. 2007. NATURAL EPIDEMIC OF FIRE BLIGHT IN A NEWLY PLANTED ORCHARD AND EFFECT OF PRUNING ON DISEASE DEVELOPMENT. In XI International Workshop on Fire Blight 793, ISHS, p. 313-320. Vincent On 18-Jun-2009, at 2:17 PM, Mark Longstroth wrote: Good Job Allen. I discussed that type of program Monday with a grower. Other sad fireblight tales. I had a grower who planted RubiJon this spring, which bloomed after normal and now have blossom blight. I suggested cutting back to 2 or 3 nodes above the graft union in an effort to save the rootstock (M26) on any tree that showed any symptoms. He also had a block of Idared on G30 which got fireblight in the fall (leaf hoppers?). He noticed 30 dead trees out of 150 this winter when he pruned but about half the planting has or is collapsing now and he will remove them all. - Mark Longstroth SW Michigan District Fruit Educator Van Buren County MSU Extension Email - longs...@msu.edu http://web1.msue.msu.edu/vanburen/disthort.htm - -Original Message- From: apple-crop@virtualorchard.net [mailto:apple-c...@virtualorchard.net]on Behalf Of Allen Teach - Sunrise Orchard Sent: Thursday, June 18, 2009 1:01 PM To: Apple-Crop Subject: Re: Apple-Crop: Fireblight on Ernst Bosch Gentlemen: I certainly agree with Mark to get rid of the culprit tree yesterday. However, let me relay an experience we had last year. On a five acre block of 3rd leaf Honeycrisp on B9 and CG 16 (tall spindle) we had some blossom blight on very late rat tail bloom and began seeing sporadic shoot blight in late June. I immediately made ugly stub cuts on the affected branches, fired up the sprayer and applied Apogee to the entire block. I continued to patrol the block and reapplied the Apogee about 3 weeks later. this is totally unscientific but we were able to avoid a disaster. Granted Honeycrisp/B9-CG 16 is not extremely susceptible but we had the trees set up with water and fertilizer to grow vigorously. Allen Teach Sunrise Orchards Inc. Gays Mills, WI P.S. Let's all dodge the severe weather the next couple of days! - Original Message - From: Axel Kratel To: Apple-Crop Sent: Thursday, June 18, 2009 11:18 AM Subject: Re: Apple-Crop: Fireblight on Ernst Bosch Mark, that sounds like good advice. Basically, I cut once, that didn't help. I cut again. if it comes back again I will yank out the tree. I do have a question for the group: When fireblight die back shows up as a result of flowers getting rained on, which of these two reasons would cause it: 1) Fireblight is systemic in the tree 2) Fireblight was brought to the tree from an outside vector. Thanks. From: Mark Longstroth longs...@msu.edu To: Apple-Crop apple-crop@virtualorchard.net Sent: Thursday, June 18, 2009 7:36:12 AM Subject: RE: Apple-Crop: Fireblight on Ernst Bosch Axel, If I had a 4 year old tree in an orchard of 200 trees with fireblight that bad, I would yank it out of the ground today! In my experience, 4 year old trees with that bad an infection don't survive. It sounds like the bacteria is running faster than you can cut and in my experience it will run very fast in wood back through three year old wood and in a 4 year old tree it is just a short jump to the rootstock. MM111 is rated as moderately resistant and I doubt it will survive with an infected susceptible scion such as you describe. If you inject strep into the tree you might save it or find out that you have a resistant strain in your orchard. Do you really want a source of fireblight in your orchard while you try to save one tree? What are you going to do if you have a storm which spreads the infection to other trees? Get rid of it now while the infection is only in one tree. It is much easier to manage fireblight if you do not have a source in the orchard. I saw
Re: Apple-Crop: Fireblight on Ernst Bosch
Hello Axel, For three consecutive years we compared sterile shears vs non sterile shears. As long as you are cutting in healthy wood (obviously) we observed the same percentage of reinfection. I'm not sure what data you have to support your claim, but our observations simply don't support what you write. In the article we conclude that speed of intervention is the key. Anything that will slow you down, including sterilizing shears or tree or wound or whatever, is more detrimental than simply cutting out diseased branches as fast as you can. The real key is to get as many of these diseased branches off the trees. This limits disease spread to other trees. Furthermore, the longer diseased branches stay on the tree, the longer they pump bacteria down the tree and into the rootstock, the higher the likelihood of death. Other considerations are minor. Vincent On 22-Jun-2009, at 4:54 PM, Axel Kratel wrote: I finally figured out what is going on. Because of the earlier infection, the tree bark is covered with fireblight bacteria even though the wood is not infected. A cut with pruning sheers inevitably re-infects the tree at the cut location. A real important step in controlling fireblight is to fully sterilize the tree, or sterilize the cut area before pruning, sterilize after pruning, and seal the cut so that the fireblight bacteria present on the bark on surrounding branches can't infect the tree. From: Vincent Philion vincent.phil...@irda.qc.ca To: Apple-Crop apple-crop@virtualorchard.net Sent: Monday, June 22, 2009 1:20:12 PM Subject: Re: Apple-Crop: Fireblight on Ernst Bosch Hi! we tried to restart trees by leaving a few nodes above the graft, but failed miserably. The darn trees never re-sprouted. We had much better success pruning out the diseased portions. We also found sterilizing shears was a waste of time. The article can be found at: Toussaint, V., and Philion, V. 2007. NATURAL EPIDEMIC OF FIRE BLIGHT IN A NEWLY PLANTED ORCHARD AND EFFECT OF PRUNING ON DISEASE DEVELOPMENT. In XI International Workshop on Fire Blight 793, ISHS, p. 313-320. Vincent On 18-Jun-2009, at 2:17 PM, Mark Longstroth wrote: Good Job Allen. I discussed that type of program Monday with a grower. Other sad fireblight tales. I had a grower who planted RubiJon this spring, which bloomed after normal and now have blossom blight. I suggested cutting back to 2 or 3 nodes above the graft union in an effort to save the rootstock (M26) on any tree that showed any symptoms. He also had a block of Idared on G30 which got fireblight in the fall (leaf hoppers?). He noticed 30 dead trees out of 150 this winter when he pruned but about half the planting has or is collapsing now and he will remove them all. - Mark Longstroth SW Michigan District Fruit Educator Van Buren County MSU Extension Email - longs...@msu.edumailto:longs...@msu.edu http://web1.msue.msu.edu/vanburen/disthort.htm - -Original Message- From: apple-crop@virtualorchard.netmailto:apple-crop@virtualorchard.net [mailto:apple-c...@virtualorchard.net]on Behalf Of Allen Teach - Sunrise Orchard Sent: Thursday, June 18, 2009 1:01 PM To: Apple-Crop Subject: Re: Apple-Crop: Fireblight on Ernst Bosch Gentlemen: I certainly agree with Mark to get rid of the culprit tree yesterday. However, let me relay an experience we had last year. On a five acre block of 3rd leaf Honeycrisp on B9 and CG 16 (tall spindle) we had some blossom blight on very late rat tail bloom and began seeing sporadic shoot blight in late June. I immediately made ugly stub cuts on the affected branches, fired up the sprayer and applied Apogee to the entire block. I continued to patrol the block and reapplied the Apogee about 3 weeks later. this is totally unscientific but we were able to avoid a disaster. Granted Honeycrisp/B9-CG 16 is not extremely susceptible but we had the trees set up with water and fertilizer to grow vigorously. Allen Teach Sunrise Orchards Inc. Gays Mills, WI P.S. Let's all dodge the severe weather the next couple of days! - Original Message - From: Axel Kratelmailto:axel.kra...@yahoo.com To: Apple-Cropmailto:apple-crop@virtualorchard.net Sent: Thursday, June 18, 2009 11:18 AM Subject: Re: Apple-Crop: Fireblight on Ernst Bosch Mark, that sounds like good advice. Basically, I cut once, that didn't help. I cut again. if it comes back again I will yank out the tree. I do have a question for the group: When fireblight die back shows up as a result of flowers getting rained on, which of these two reasons would cause it: 1) Fireblight is systemic in the tree 2) Fireblight was brought to the tree from an outside vector. Thanks. From: Mark Longstroth longs...@msu.edumailto:longs...@msu.edu To: Apple-Crop
