This blog is part of a series, click here to view all blogs in this series
The first #wildplantdisease challenge set by @wildflower_hour and @BS_PP resulted in over 700 tweets and 4 million potential views on Twitter from activity 8-9pm BST on Sunday night. Posted pictures included a range of diseased plants displaying galls, smuts, rusts and yellowing (chlorosis) of plant tissue.
Look out for rusts, blotches, streaks, mottles, galls & mildews on wild plants, that’s the challenge for #Wildflowerhour this Sunday as we team up with the wonderful British Society for Plant Pathology to explore the amazing world of #WildPlantDisease! https://t.co/jIDjIqvJ5R pic.twitter.com/jlhhWpyPPk
— wildflowerhour (@wildflower_hour) August 10, 2020
Last week’s challenge (launched 10th August) was in contrast to the usual wildflower spotting challenge, where followers of @wildflower_hour spend an hour posting rare, beautiful and interesting photos of wildflowers taken from across the UK and Ireland.
British Society for Plant Pathology member and wildflower enthusiast, Nichola Hawkins suggested an exploration of wild plant disease and a group was set-up with Phil Taylor (CABI), Pietro Spanu (Imperial College London), Eric Boa (University of Aberdeen), Fay Newbery (RHS), Joshua Styles (Wildflowerhour) and Rebecca Wheeler (Wildflowerhour). (Read more about Wildflowerhour team members below.)
On Sunday 16th August @wildflower_hour @BS_PP @BSBIbotany and a host of volunteer experts were on hand to monitor an hour of storming Twitter with some fantastic images of #wildplantdisease. An estimated 654, 083 accounts were reached through major Twitter influencers like @seed_ball @Britnatureguide@NatureUK @MikeH_PR @KamounLab @makinggardens @GreenHampshire @issybryonyh @NearbyWild @botanyone @HTAnews and many more.
Over 560 pictures were Tweeted for #wildplantdisease of which a small portion are highlighted: Insects stole the show with their flamboyant galls, for example: the perfectly red and round Rose pea gall on Dog rose as posted by @seed_ball; the subtle Artichoke galls on English Yew caused by gall midge Taxomyia taxi posted by @nervousbotanist and the exotic Robin’s Pincushion on Rose caused by the tiny larvae of a gall wasp posted by @ChicksChange. Not to mention the rare Crimson Harebell aphids shared by @Joshual951. Prolific leafminer infestations, mainly on Horse Chestnut, were posted from multiple tweeters. Thankfully, @Entoprof was on-hand to confirm many infestations and @AndrewSalisbur2 to ensure accurate identifications.
Fungal diseases were perhaps most dominant and Smuts featured highly as floral pathogens, causing black sporulation of the anthers of many wildflowers – particularly White and Red Campion. Rusts and Powdery Mildews were to be found on a range of wildflower plants from Deadnettle and Hogweed to Oak. The aecial galls of rusts were not to be confused with the impressive spangle galls of a number of wasps on the undersides of afflicted leaves. Tar spot was to be found on many tree leaves.
Oomycetes or water moulds – a group of micro-organisms not to be mistaken for fungi – made an appearance mainly through Albugo candida or White blister rust, seen above on ‘Honesty’ seed pods.
@luca_steel of the #PlantDefenders with Girlguiding highlighted her first ever #wildplantdisease find of Phragmidium violaceum or Violet Rust on Bramble and @wheatpath Frederic Suffért featured a number of beautiful wild plant diseases found in France, including symptoms on plants alongside microscopic images of the microorganisms responsible.
Viruses appeared with a range of symptoms from striking vein yellowing to deep red bramble leaves pointed out by @Blisteredcanker and @plantpathdog, with comments from @Prof_GD_Foster.
Weird and wonderful plant disease symptoms were spotted including Eric Boa’s Witch’s broom-like symptoms on Willow (tweeted by @BS_PP) and Fay Newbery’s @FayrnHawk spot of Witch’s broom on Hornbeam. There could have been more identification of bacterial diseases…but maybe that is for another time. See @CuongVHan’s tweet from South Korea/Vietnam as a last minute entry.
Highlighting biodiversity and the ecological complexity of the #wildplantdisease world, Nichola Hawkins spotted a rust infecting a hemiparasitic plant: Red Bartsia is a plant which grows from the roots of grasses and Coleosporium tussilaginis the rust fungus which infects this plant.
To top the insects and micro-organisms threatening wildflower health during #wildflowerhour @PietroSpanu shared his discovery of the fully parasitic plant Dodder (or Cuscuta) from the banks of the Thames.
Sometimes the plant Is the disease.
In this case dodder (Cuscuta) pic.twitter.com/G4IZRc2Sj7
— BSPP (@BS_PP) August 16, 2020
Wildflowerhour is an initiative based in the UK, supported by the Botanical Society for Britain and Ireland, but #wildplantdisease included tweets from across the globe and across time-zones (hence the hour was extended!).
With thanks to Nichola Hawkins and Joshua Styles as wildflower and plant pathology specialists, and Rebecca Wheeler who runs the @wildflower_hour account.
“I’m Nichola Hawkins. WildFlowerHour followers might know me as a keen amateur botanist and member of the Wild Flower Society. BSPP members, on the other hand, might know me as a postdoc researching plant pathogen evolution and fungicide resistance. I’m really excited about the opportunity to bring together my interests in wild flowers and plant pathology for the #WildPlantDisease challenge!”
Rebecca Wheeler @botany_beck on Twitter runs the @wildflower_hour @WebsWild accounts and leads the #wildflowerhour challenges:
“I am a horticulturist and forest school practitioner and I am very passionate about wildflowers, in particular native orchids. I am completely obsessed with all nature and I am particularly fascinated with how different species are interlinked and dependent upon one another. I am really looking forward to the #wildplantdiseasehealth challenge this Sunday, a very exciting new challenge for #wildflowerhour!!”
“Hi, I’m Josh Styles and I’m a 25 year old ecologist and general plant obsessive. I’ve had an interest in plants since around the age of 6, and over the past couple of years have developed a keen interest in smuts and rusts”
*Estimations of accounts reached and potential views are based on number of followers for each user tweeting or retweeting #wildplantdisease. Data taken from Twitter.com and socialbearing.com.