2017 AYLS Summary

Another year has passed and still no answer to what is causing AYLS!

Only a handful of new reports came in during 2017, all indicating AYLS is PRESENT except one personal observation that AYLS was ABSENT from arguta & deliciosa vines in Port Orchard, Washington. Those plants were in a hoop-house, possibly indicating that AYLS might be an Environmental problem rather than a Disease.

Two locations in Western Washington where the growers have consistently reported since 2014 that AYLS was ABSENT were refuted by personal observation that showed AYLS is PRESENT! Those observations now confirm that AYLS is PRESENT in all but about four locations reported from Abbotsford, B.C., Canada to south of Centralia, Washington. It is imperative that all people actually take the time to look closely at all vegetation on the vines before submitting a report. Many more reports are needed from around the World to obtain an idea of where AYLS is really PRESENT or ABSENT before an answer about the cause can be found.

One interesting observation is that AYLS emergence here in Seattle coincides with approximately 1,500 degree days as computed by the US.PEST.org website using a base of 41°F in this calculator for my local weather station (which may be reset using the Map function for a weather station in your area if you live in the USA and some parts of Canada):

Again, if you know of any Actinidia growers worldwide from areas that haven’t reported, please take the time to let them know about this site, and ask them to submit a Report using the form available on either the About AYLS or Map of AYLS locations Worldwide pages of this site.

Happy Growing,
Bob Glanzman
Seattle, WA USA


AYLS is back again for 2017, later than past years!

If you haven’t already signed up to “Follow” this site, please do so using the link below so you will get automatic e-mail notification of any new posts.

AYLS first appeared at my place in Seattle this year on a potted seedling arguta on June 25 2017, about 25 days later than 2015 & 2016!  The late appearance caused me to question what triggers the onset of AYLS?  Examining the uspest.org website came up with one answer, Degree Days!  Based on the onset of AYLS in 2015 & 2016, and estimated time of onset in 2014, it appears that there is a correlation between onset and about 1,500 degree days as calculated by their model for Seattle station C6259.  In the USA and parts of Canada, you can find your local station using the Map at this link:  http://uspest.org/cgi-bin/ddmodel.us

None of the Plant Pathologists on my e-mail list have responded yet to my inquiry as to the apparent Degree Day correlation and what that might suggest may be the cause, but I will do another post if it suggests a possible cause.

Since June 25, it has become visible on potted kolomikta & melanandra plants as well as more argutas.  On July 4, AYLS appeared on a single leaf of one of my in-ground argutas so it is progressing, but not as rampant as in 2014.

Anyone who grows Actinidia vines should fill out a Report form on either the Home page or the Map of AYLS locations Worldwide page.  The Report form has fields for both AYLS is PRESENT and AYLS is ABSENT at your location.  Knowing where AYLS is ABSENT is just as important as knowing where it is PRESENT!  If AYLS is PRESENT on your vines and you know the date symptoms first appeared, please report that date in the comments field.

Bob Glanzman,
Seattle, WA. USA

2016 AYLS Summary

2016 has been a disappointing year due to lack of progress in finding the cause of AYLS!

There were a number of new Reports in 2016 of both ABSENT and PRESENT.  The Reports show that AYLS is PRESENT in more of Western Washington all the way North to Abbotsford BC Canada, and in other US States as well as locations in Europe.  Several of these Reports have not been confirmed with photographs however.

My conclusion is the 2016 Reports do not indicate that AYLS is spreading, but are merely filling in the blanks in our understanding of current distribution.  Hundreds if not thousands or additional Reports from around the World are needed to fully understand the extent of AYLS.

An additional test of affected leaves resulted in NEGATIVE for the presence of Bacterial and Fungal Pathogens.

Over the past three years of active searching for the cause, I believe that we can rule out:       1. Cultural Practices due to distribution patterns.    2. Bacterial Pathogens due to test results.    3. Fungal Pathogens due to test results.    4. Nutrient causes due to two fertilized test plots, both of which showed AYLS symptoms although at a diminished level compared to unfertilized plants.

That leaves several possibilities:    1. Viral Pathogens which will only be either confirmed or denied by “Next Generation Sequencing” to search for the presence or absence of a Virus.  This process is far beyond my means and is not likely to occur unless some University takes it on as an unfunded Research Project.    2. Environmental Causes, which will require thousands of Reports from around the World to get a clear idea of Distribution patterns in order to focus on possible Environmental Factors.    3. The possibility that was suggested to me this year that AYLS is “Everywhere” in Actinidia Species.  I believe this is a far-fetched idea due to Reports of ABSENT from trusted Actinidia Researchers and Growers in several Countries, but without personally observing plants outside the Puget Sound Region of Western Washington, I can’t definitely rule out this possibility.  A trip to Actinidia plantings in Oregon next Summer is on my list of things to do.

Since my proactive efforts to obtain Reports from growers Worldwide have generated inadequate responses (including NO Reports from the Southern Hemisphere other than a 2014 contact from New Zealand), I will limit my efforts in 2017 to periodic new posts on this page and adding any Reports that are submitted to the “Map of AYLS locations Worldwide” page.  The outreach efforts are now YOUR responsibility to contact other Actinidia growers you know and Fruit Organizations you are a Member of to let them know about this Site!

Thanks,   “kiwibob”,  Seattle, Washington, USA

Please take the time today to sign up to “Follow” this Site on the link on this page so you will get automatic e-mail notifications of any new posts.


Time to check your Kiwi plants for AYLS

The first signs of AYLS were visible on potted Actinidia vines on June 1 and have since appeared on 7 (arguta, hypoleuca, kolomikta, macrosperma, melanandra, polygama, & tetramera) of my 12 Actinidia species as well as on plants in other locations in Seattle.  Symptoms are now becoming visible on Hardy Kiwi vines planted in the ground.  It’s time to start checking your Kiwi plants for AYLS.  If symptoms aren’t visible yet, check your plants about every 10-15 days from now until early September.  As soon as symptoms are visible, please report PRESENT as noted on the “About AYLS” page.  If no symptoms are visible by September 1, please report ABSENT at that time.

Since all Bacterial, Fungal, and Viral tests thus far have returned NEGATIVE, we need to get a much better idea of where AYLS is affecting Actinidia vines to focus on the possible cause.

Thanks,   “kiwibob”,  Seattle, Washington, USA

AYLS is back again for 2016!

AYLS was probably visible a few days ago but today was the first time I noticed the signs of AYLS in some of my potted seedling plants.  It can be expected to be visible on plants in the ground later this month and should be affecting almost all Actinidia species before mid-July.

During 2016 we need to gather many more reports of ABSENT or PRESENT to get a better idea of the Worldwide Distribution of AYLS, so please let anyone who grows Actinidia vines know about this Site.

Please sign in below to “Follow” this Site in order to get automatic notification of any new Posts.

Thanks,   “kiwibob”,  Seattle, Washington, USA

2015 Summary Report

Although AYLS symptoms were not as severe as in 2014, as 2015 ends, there is still no answer of what causes AYLS!

A new round of tests in 2015 for Bacterial, Fungal, and (Potyvirus complex) Viral causes all came out Negative!

Two cases that I followed of presumably “clean” Actinidia arguta plants purchased in 2014 indicate that AYLS is communicable!  The first case consisted of 2 vines purchased in early Spring 2014 and planted in the ground in Seattle.  By mid-July 2015, one of the two showed clear AYLS symptoms.  The second case is one vine purchased in Summer 2014 and still in a pot in Seattle.  It showed clear AYLS symptoms by mid-August 2015.

Several new reports of PRESENT were submitted in 2015, all from King & Pierce Counties in Western Washington.  These reports were the first from each specific location and should not be construed as a spreading of AYLS.  Two reports of ABSENT were submitted in 2015, one from Corvallis Oregon, and the other from Delaware.  Many more locations need to report if AYLS is ABSENT or PRESENT for the Worldwide Map of AYLS to become a useful tool in the search for a cause.

Hopefully 2016 will bring answers instead of more questions.

Happy New Year,   “Kiwibob”, Seattle Washington, USA

It’s 2015 and AYLS is back again!

It’s June 21, 2015 and as I expected, AYLS is back again this year in Seattle.  Symptoms began appearing on three leaves around June 1 and are now apparent on leaves of most smooth-skinned Actinidia species in my collection in rooted cuttings, potted plants, and plants in the ground.  One nearby Home Grower has reported AYLS on both his argutas and kolomiktas.

Since no progress was made in 2014 on identifying the responsible pathogen, it’s time for everyone who views this Blog to send the link to all Actinidia Growers they know, and to any Fruit Growing Groups you are a Member of.  Particularly important is enlisting the help of Plant Pathologists, so if you know any, make sure to send them the link and ask for their help.  Please sign in to “Follow” this Blog so you will get an automatic e-mail notification of any new posts, of which this is only the fourth post since the Blog was created in August 2014.  By working cooperatively together, we might be able to identify the cause of AYLS in 2015!

I’ve added a new page for AYLS photos taken in 2015. If you reported that AYLS was PRESENT or ABSENT in your Actinidia collection in 2014, please send me a report for 2015 as soon as you see AYLS appear, or around late August if AYLS is ABSENT from your collection, giving me your location (nearest town), which Actinidia species you are growing, and an e-mail address so I can contact you. If AYLS is PRESENT, please take 3-4 digital photos about 200-400kb in size and send them to the Blog email address.

Many of the affected leaves in my collection have small insect bodies on the back side of the leaf.  I suspect that AYLS is transmitted by insects and know of two test cases here in Seattle where Home Gardeners purchased Actinidia plants during 2014 that came from sources that don’t have AYLS.  Later this Summer, I’ll report whether those plants have been infected since their purchase and planting in the ground last year.

Also planned for 2015 is the addition of a Researchers page which I hope will facilitate communication between Plant Pathologists, Actinidia Researchers, and Agriculture Extension Agents.

Again, please sign up to “Follow” this Blog so you will get automatic e-mail notifications of any new posts.

Happy Growing,
Seattle, Washington, USA

Where do we go from here?

The most important thing you can do to advance the effort to find the cause of AYLS is to sign up to “follow” this Blog and encourage other Actinidia Growers and Researchers to visit and “follow” as well!  Including the original August 3 post, this post is only the third one that would activate e-mail notice of an update.

If you are a Plant Pathologist or know anybody in that line of work, signing up to “follow” this Blog is especially important.  To date, the active participation of Plant Pathologists in the search for the cause of AYLS has thus far been missing!

As dormancy’s grip reaches all of the Northern Hemisphere, it signals a lost opportunity to find the cause of AYLS in 2014.  Attention will now shift to the Southern Hemisphere for the next six months, to determine locations where AYLS is ABSENT or PRESENT, and if PRESENT to hopefully find the cause. Everyone who sees this post is encouraged to contact any Actinidia Growers they know, especially those Growers in the Southern Hemisphere, and invite them to visit this Blog and to report if AYLS is ABSENT or PRESENT in their plants.

Many more reports of ABSENT or PRESENT are needed to make any sense out of the distribution of AYLS.  Considering that AYLS is PRESENT in all 19 of 19 locations observed or reported throughout the city of Seattle and in several nearby communities, it appears AYLS is easily transmittable from plant to plant over distances that suggest insects are the likely transmission vector.

Again, please sign up to “follow” this Blog.  Only by working together will we find the cause of AYLS!

Kiwibob Glanzman
Seattle, Washington, USA

45 days but no answer yet!

The AYLS Blog has been up and running for about 45 days now but there is still no answer about the cause of AYLS!  Two possibilities have been raised by researchers, that it may be a Bacteria, or that it is caused by Phytoplasma.

Much more information is needed about the Worldwide Distribution of AYLS so whether you are a researcher, Extension Agent, Master Gardener, Fruit Club Member, Commercial Grower, or just a Backyard Grower, please use your networks and encourage anyone who is growing Actinidia vines to reply to this Blog whether AYLS is ABSENT or PRESENT.  It is equally important to know where AYLS is ABSENT as where it is PRESENT!

If you are a Plant Pathologist, please sign up to “Follow” this Blog.  If you can help with finding the cause through Labwork, please let me know.

Onward,   Kiwibob, Seattle

Welcome to the AYLS Blog


Welcome to the AYLS (Actinidia Yellow Leaf Spot) Blog.  This Blog is intended to be a forum for gathering information about the Worldwide distribution of AYLS to help determine its cause.  If you grow any species of Actinidia (Kiwifruit relatives) you can help by submitting information as noted on the “About AYLS” page.  If you are involved in Actinidia or Horticultural Research and would like to help, please let me know.

By working together, hopefully we can find the cause of AYLS.


“Kiwibob”   Seattle, Washington, USA

By kiwibobnow Posted in Purpose