Dying plants in the fynbos, South Africa

jmhulbert's picture

The purpose of this project is to create a database of dying plant reports in the fynbos. With your contributions, we can learn about plant disease in the fynbos, ultimately benefiting the conservation of the biodiversity in the biome. Sampling will be coordinated for each report to determine whether Phytophthora species are involved. Phytophthora is a group of microscopic organisms that cause disease in plants. In Greek: Phyto = plant, phthora = destroyer. Phytophthora cinnamomi is one species known to be present in the fynbos, causing root rot of many plant species in the Proteaceae. Join us in the hunt for pathogens like Phytophthora cinnamomi. You could discover a species that has never been found or studied before!

This project is part of Cape Citizen Science. By reporting the dying plants that you see, you will be contributing to research about plant disease! You be the scientist! More information at http://citsci.co.za

Join us in the first phase of the project! To report a dying plant, add the tag dyingfynbos to the observation.

Please do not hike off-trail in National Parks - please be respectful of park policies.

DyingFynbos_1.8

Observations in your project area

Comments

Tony Rebelo's picture

How does one contribute to

How does one contribute to this collection?

I would argue that if it is Phytophthora then the filter Taxonomy = Phytophthora would be needed.

But if it is to collect observations of dead plants, then it is best done by a tag. But which tag?? I think that one may exist already, but I need to look it up. Later ...

Andrewm's picture

Any luck?

Any luck?

jmhulbert's picture

Hi Tony,Great suggestion. I

Hi Tony,

Great suggestion. I added the tag dyingfynbos, but let me know if you dig up a previously used tag for dying plants. Also, is there a way to enable notifications when someone posts/comments to the project?

Joey Hulbert
Cape Citizen Science
http://citsci.co.za
Report dying plants in the fynbos here: http://www.ispotnature.org/projects/dying-plants-in-the-fynbos-south-africa

Tony Rebelo's picture

old observations

You are welcome to invite anyone to post observations, or on existing observations to post tags: that is a good way to collect useful observations.

Tony Rebelo's picture

notifications

Sorry: iSpot has a policy of not bothering you.

If you have contributed to an observation (ID, comments, replies, I agrees) then iSpot will notify you in your changes - which are stored for 30 days.

For observations in your project, simply look in the List Tab above, whenever you wish. To get the total of observations so far, see the top of the Map Tab.

jmhulbert's picture

Thanks Tony, How do I go

Thanks Tony,

How do I go about getting exact coordinates for the observations that are added? This is fundamental to using Ispot as a research tool.

Thanks

Joey Hulbert
Cape Citizen Science
http://citsci.co.za
Report dying plants in the fynbos here: http://www.ispotnature.org/projects/dying-plants-in-the-fynbos-south-africa

Tony Rebelo's picture

depends

Quickly: by looking at the map on each observation: the coordinates are shown there.

En bulk: you need to formally request the data from SANBI - your project proposal should be adequate, and I can provide it quarterly or annually as you prefer, in excel or csv format as you prefer.

jmhulbert's picture

Thank you!

Sounds good. Thank you for the information Tony.

Joey Hulbert
Cape Citizen Science
http://citsci.co.za
Report dying plants in the fynbos here: http://www.ispotnature.org/projects/dying-plants-in-the-fynbos-south-africa

jmhulbert's picture

Contributing

I have added the tag 'dyingfynbos' to the project. Please tag observations with dyingfynbos in the details if you would like them to be included in the research! You can also submit observations as plants, because we are observing symptoms that the plant is expressing rather than signs of the pathogen—Phytophthora are microscopic! :) If possible, please report dying plants rather than dead plants, but know that it is also valuable to know where dead plants are! Also, please note that we are not studying plants killed by fire in this particular study. Thank you!

Joey Hulbert
Cape Citizen Science
http://citsci.co.za
Report dying plants in the fynbos here: http://www.ispotnature.org/projects/dying-plants-in-the-fynbos-south-africa

Tony Rebelo's picture

codicil

From: http://www.ispotnature.org/node/740138#comment-385926

This is senescence.

It is a bit like categorizing the causes of death in people over 100 years old. The actual cause (stroke, heart attack, pneumonia, cancer, accident, predation, parasites) is really irrelevant. Collecting gut, skin and blood parasite, bacteria and viruses to determine the role in the death is rather pointless too!

It is no different with plants. At this age, if any pathogen is relevant, it is only as a contributing factor to the inevitable.

Tag added: but as fynbos death, not killed fynbos.

Tony Rebelo's picture

Would you like to test a theory of mine?

Fynbos is unusual. There is no effective recruitment in between fires (i.e. in the year or two after a fire). Why?

There are lots of theories. Obviously fire clears everything and gives the best odds for establishment. By why dont more plants try and establish between fires?

Theories include:
In older veld there are:
more established plants: direct competition for resources that seedlings cannot cope with;
more established plants: competition for water especially in summer so that seedlings spend too long a period drought stressed and die;
more established plants: some of which produced allelopathogens which kill seedlings;
more cover: allowing higher levels of rodents and insects that eat seeds and especially seedlings;
more established plants: which accumulate pathogens and parasites with veld age at levels below threshold for adults, but far too abundant for seedlings;

One does find occasional seedlings between fires, usually in disturbed areas, alongside paths (= disturbed areas?), and in very old and senescent veld.

So my theory is. Young veld for obligate reseeding species is relatively pathogen free: the fire has removed them all. As the veld ages, pathogens (and seed predators, and pollinators) recolonize the area and become more abundant.
The corollaries are:
* resprouters have to cope with their pathogens better.
* close relatives and individuals of reseeders closer to resprouters are likely to be more quickly infested.
* small fires* and patchy fires are detrimental as the pathogens colonize too quickly - hindering recruitment. (* what size is too small? -m2, ha, km2, Mm2)
* there will be gradient from the edge of a fire inwards of pathogen and parasite abundance and rate of colonization.
* the same applies to animals, especially tortoises - the more adults survive the higher the pathogen load. If sufficient animals survive, the fire is irrelevant to pathogen levels. But some tortoise species, in which almost all the adults are killed, might rely on this to keep pathogen levels low.

I am not certain what happens in very old veld: do parasites decline when their hosts do, or do they hang around better?

or is all of this irrelevant? Am I clutching at straws and burning embers?

jmhulbert's picture

It is testable

Hi Tony,

I am intrigued. We could design a study to measure the gradient of pathogen abundance from the edge of a fire, inwards and outwards. We could run transects perpendicularly from the fire line (assuming there is some sort of line), mapping reseeders and resprouters, and taking soil/rhizosphere samples to quantify pathogen abundance. If I were to do this study, the metric would probably be Phytophthora species richness or number of P. cinnamomi isolates recovered under a rigid sampling design.

I would be willing to conduct a study like this if we could get crew involved, or some other group to help sample. Also, we would probably want an honors student from one of the universities to help isolate from the samples and maintain the culture collection. It could be a great project.

Lets chat more!

Joey Hulbert
Cape Citizen Science
http://citsci.co.za
Report dying plants in the fynbos here: http://www.ispotnature.org/projects/dying-plants-in-the-fynbos-south-africa

bergnimf's picture

Re-establish

Will your study also look at ways to re-establish once you understand what is causing the deaths? Even if it would mean human-induced re-establishment.

Tony Rebelo's picture

You seem to be assuming

1. That deaths are actually occurring at significant levels.
2. That deaths will lead plants dying before they can set seed
3. That deaths will result in local extinction.

and therefore that some action might be necessary.

One step at a time: I dont think that any locally indigenous pest species will be an issue.
At present I dont see any significant population reduction attributable to local pathogens.

However, if this study shows otherwise, then it might be time to address these issues.

The biggest issue though - similar to one faced at Kirstenbosch in their flower beds where pathogens have reached pandemic proportions for some species - is how do you reintroduce the species without controlling the pathogen? If the pathogen is still around what is the point?
And so:
(1): killing the pathogen will kill hundreds of other species of useful pathogen-relatives. And probably destroy the ecosystem.
(2) breeding pathogen resistant plants will not be easy, cheap, and is bound to fail (because most breeding attempts result in domestication-by-accident and domestic plants need fertilizer, insecticides, fungicides, water and tender loving care: which dont exist in Fynbos.

So just what are you assuming and what are you proposing?

jmhulbert's picture

Good question!

Hi Bergnimf,

Thank you for joining the discussion! Tony made some good points in response to your question, but I will add my perspective here too. I am a big fan of applied research so I will try my best to make it relevant to growers and helpful for conservation practices.

As you alluded to, the first step is to identify the cause of death. It may be abiotic (drought or fire), but it could also be an insect or pathogen (disease causing microbe). Once we identify the species responsible, we can decide whether controlling the pathogen is feasible. Depending on whether the species causing disease is a native or introduced species, we may try to eradicate it from the area (and prevent further spread elsewhere). However, if the organism is native, it is likely widespread and it may be more feasible to focus on saving the host species (e.g. with the development of a resistance program where plants are bred to be resistant to the disease). This also depends on how important (or how endangered) the plant species is.

As Tony mentioned, some control methods (fumigation, fungicides, etc.) can have unwanted consequences on non-target organisms. However, there are also safer control methods that may be feasible, such as soil solarization, or even simply just rotating crops.

Identifying the species that is causing the disease is critical for making decisions and determining where to invest resources.

Consider this: some Phytophthora species (plant killing microbes) are considered generalist pathogens because they infect many different plant species (e.g. Phytophthora cinnamomi—causing root rot in many proteas and even avacados), but other species (e.g. Phytophthora infestans—the irish potato famine and potato late blight) are known as specialists because they can only infect certain plant species. Now, depending on which type (generalist or specialist) you are dealing with, it will determine whether re-establishing a community is feasible.

In addition, once the responsible organism is identified, we can plan/justify further research around controlling that organism to allow reestablishment.

Thanks again for joining the conversation! Please feel free to contact me with specific questions or continue the dialog here!

Joey Hulbert
Cape Citizen Science
http://citsci.co.za
Report dying plants in the fynbos here: http://www.ispotnature.org/projects/dying-plants-in-the-fynbos-south-africa

miked's picture

Presumably since you are

Presumably since you are citizen science organisation you will be getting the general public to help with ideas of how to design the experiment even if it is based on Tony's initial comments.

Then those members of the public (dog walkers in UK) would record the area in some way each week looking for signs of growth/disease and hoping it is not them who are carrying the disease on their shoes. In uk there are disinfectant stations to wash your boots in areas with disease, although not sure if they are just cosmetic to raise awareness.

Have you got old photographs of fynbos with enough detail to see if there were any dead or dying plants in olden times, before there was the current worry about disease. might be another citizen science project ask for fynbos photos from more than 10 years ago and look for dead areas and preferably try to get a reasonably accurate location, might not need accurate locatoin if you could just estimate % of dead plants and compare with now. If people scan them and put on website then anyone could do this analysis.

jmhulbert's picture

Brilliant

Hey Mike,

Thank you for the suggestion! I like it, great idea. And yes, we are certainly open to ideas for projects from citizens. I will add it as a 'mini-project' to our website (http://citsci.co.za). It would definitely be interesting to go back to the sites in the pictures and compare. If the area hasn't had a fire, would it still look the same? Or did Phytophthora eliminate a certain species from the area? Sounds fun!

Several studies were published in the late 70s and early 80s acknowledging Phytophthora root diseases of many fynbos species, but none that I have come across actually quantified the amount of disease. We plan to revisit some of those study areas, and of course, anyone is welcome to join us in the sampling activities.

We would also appreciate any suggestions for areas that people knew had Phytophthora issues at some point in the past. Is there an old nursery or an old orchard that you know the landowner of?

Thanks again for sharing the idea with us!

Joey Hulbert
Cape Citizen Science
http://citsci.co.za
Report dying plants in the fynbos here: http://www.ispotnature.org/projects/dying-plants-in-the-fynbos-south-africa

miked's picture

Have just looked through my

Have just looked through my 2005 Fynbos photos which have geolocations and quite a few of them do show plants that look as though they are dead/dieing, however as Tony says in most cases the 'death' looks as if it is associated with senescence or fires e.g. leggy heather plants that have just one or tips with green growth and most of the plant is grey and dead.

Will be tricky for untrained person to distinguish between the different forms of loss of growth so will need good ID material to help with telling the different forms of loss of growth apart. Back here in UK there is also the situation where heather plants can look as if they are senescent but it is actually cased by heather beetles causing complete defoliation of large numbers of plants.

jmhulbert's picture

True

Hey again Mike,

That is wonderful. Isn't it amazing how much dieback/disease you see once you start looking for it? You know you are a plant health specialist when you get excited seeing it.

You are absolutely right, it is difficult to determine the cause of a lot of the symptoms we see from just a photograph—especially with microscopic pathogens. Many different causes can bring about the same symptoms as well. That is why we are committed to visiting and sampling (pending permission) the locations submitted on ISpot. However, through visiting these sites and physically sampling the plants, we should start to develop the skill to recognize patterns on certain species, ultimately training our eyes. Then we can disseminate that information to other plant health specialists, gardeners, and citizen scientists.

For example, we hope to be able to say with some confidence that symptom x on this plant species 1 is likely caused by Phytophthora, where another symptom, symptom y, on plant species 2 is caused by something else, such as drought.

Great thinking!

Joey Hulbert
Cape Citizen Science
http://citsci.co.za
Report dying plants in the fynbos here: http://www.ispotnature.org/projects/dying-plants-in-the-fynbos-south-africa