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So here's the latest weird nature thing I've run across. I'm currently in Vancouver (WA, not BC) and parked next to this in a cute little neighborhood. I noticed this well-established Chinese arborvitae (Platycladus orientalis) in someone's yard had these weird sprigs of pale yellow, almost cream foliage. My first thought was that somehow these were developing without chlorophyll, maybe through a genetic quirk, but the pattern was too uneven.

Upon further research (as in, I put it on iNaturalist) it looks like the culprit is a fungus, Pestalotiopsis funerea, one of several plant pathogens that can cause tip blight. I'm used to seeing brown foliage as a sign, such as on western red cedar (Thuja plicata), but the lighter hue threw me off since I usually see it in plants that developed without chlorophyll.

Apparently it especially affects older foliage on the tree or bush, especially that which is very crowded and therefore more prone to dampness and fungal infections, and in individuals that are more stressed due to heat, drought, or cold spells. Recommended treatments include pruning affected branches while sterilizing your loppers in between each branch, and keeping the plant well-trimmed so the foliage doesn't become too crowded, as well as watering it plenty to avoid drought stress.

#nature #weird nature #plants #botany #plant diseases #plant pathogens #fungi #nature photography #gardening #horticulture #ecology #PNW #pacific Northwest #Washington #Arborvitae

Puccinia urticata on Urtica dioica

It’s hard to walk by banks covered in common nettle without noticing this fiery and gruesome rust fungus taking hold of and deforming the plant’s limbs.

It’s best described as a species complex with a life cycle which might alternate between two hosts- in the British Isles often a nettle (U. dioica or U. urens) and a sedge (mostly Carex sp.), but its ‘sub-species’ can also be found on Aster and Ribes.

Here you can see some beautiful up-close photos of its structures.

#puccinia urticata #rust fungus #basidiomycota #fungi #mycology #urtica dioica #common nettle #urticaceae #botany #plant pathogens #scotland #plantblr #gardeners on tumblr #plants

Ringless honey mushrooms (Armillaria tabescens) have bioluminescent mycelium. They vary in color quite a bit, as seen here.

#mushrooms #fungus #fungi #nature #mycology #ringless honey mushroom #pathogens #plant pathogens

Fomitopsis betulina

This common bracket fungus, the birch polypore or razor strop, is widespread throughout the northern hemisphere and the main cause of brown rot on birch (Betula sp.) trees. It is well known due to its long history of traditional uses and pieces of it were found among the belongings of Ötzi the Iceman, a mummified man who lived over 5000 years ago and was found in the Alps between Italy and Austria in 1991. The birch polypore is edible when young, but it has mostly been used for its medicinal value, supported by modern pharmacological research which has highlighted a wealth of possible further uses. From wound dressing to brewing as tea, its antibacterial, anti-inflammatory, antiseptic and analgesic properties made it a valuable species in the folk medical practices of Europe from antiquity up until modern times. Maybe less importantly, it has also been used to refine the sharp edge of razors, which gave it the common name ‘razor strop’.

Interesting further reading from the World Journal of Microbiology and Biotechnology

#fomitopsis betulina #birch polypore #birch bracket #razor strop #fungi #mushrooms #mycology #plant pathogens #betula #medicinal fungi #foraging #woodland #plantblr #gardeners on tumblr #horticulture #folk medicine #scotland #botany

Uromyces viciae-fabae, Broad bean rust

Together with my allotment, I inherited a few crops sown by the previous tenant, one of these being broad beans (Vicia faba). As the plot had laid abandoned for a while, the plants had suffered from the period of drought we experienced earlier this summer so weren’t doing particularly well at the point I took over, but I tried to revitalise them with abundant water and fertiliser. It seemed to work, as they started flowering again and I even got to harvest one single pod, but it was already getting late in their productive season, and shortly after the first signs of broad bean rust started becoming evident, so I ended up cutting them down and disposing of them.

This particular fungal disease affects only this species, and tends to overwinter as hardy spores in the soil, so I will avoid growing broad beans again, at least in the same raised bed. It can be controlled with fungicides during its early stages, but using resistant cultivars is the best practice, and plants are more likely to be affected towards the end of their cycle anyway.