ASH TREE Biodiversity

ASH TREE BIODIVERSITY / Gary Lincoff, 2017


5 Kingdoms interacting with Ash Trees 


No tree is an individual; all are communities of organisms changing over the course of a year and throughout the life and death of a given tree. Even as a tree is reduced over time to soil, a succession of organisms appear and disappear, as the tree is debarked and broken down to house and feed a multitude of organisms. Epiphytes, endophytes, parasites, decomposers, symbionts all have roles to play, as do some things flying by, crawling up, or blown by wind, looking for a meal or shelter or both: a tree is a microcosm of all the kingdoms of life. Know a single tree thoroughly and you know more about life and evolution than any world traveler can ever hope to attain.


6 Ash trees in Central Park


Fraxinus americana (White Ash)

         Susceptible to EAB, ash tree flower gall mite,

         Ash tree leafcurl aphid


Fraxinus excelsior (European Ash)

         Susceptible to Chalara fraxinea (Hymenoscyphus fraxineus)


Fraxinus ornus (Flowering Ash)

         Susceptible to scales, root rot fungi, sooty mold, Verticillium wilt


Fraxinus pennsylvanica var. pennsylvanica (Green Ash)


Fraxinus pennsylvanica var. subinegerrima


Fraxinus profunda (Pumpkin Ash)

         Susceptible to EAB, Neonectria ditissima (Nectria galligena) (coral spot) canker, Ganoderma rot, Oyster mushroom bark saprotroph, etc.


Note: on determining the age of an urban tree:

Different websites are all over the map on just how old a given tree is – without cutting it down or coring it – but just by estimating its age by measuring its circumference and then a little division and multiplication. There seems to be some agreement that the age of a Green Ash can be approximated simply by measuring its circumference at 4 ½ feet from the base of the trunk: its age in years is about equal to its circumference in inches.




         ? Knothole Moss (Anacomptodon splachnoides) ? and others (to be determined)

        ? Threadbare Moss (Anomodon tristis)

Green Algae…….

Coccomyxa spp.– single-celled Green Alga




EAB – Emerald Ash Borer – Agrilus planipennis

         Forest Health Center research update:

“Ash endophytes may provide a new bio-control option for fighting the emerald ash borer”

US Forest Service & Forest Health Research `and Education Center – Dr. Tyler Dreaden


Ash leafcurl aphid – Prociphilus fraxinifolii

         Aphid living in sclerotia of the bolete

         Boletinellus merulioides


Ash flower gall mite  (aka Cauliflower gall mite)

         Aceria (Eriophyes) fraxinivorus


Ash bud moth (Prays fraxinella)


Some Birds that feed on Fraxinus seeds:

         Ducks                                Cardinal

         Finch                                 Grosbeak

         Finch                                 Cedar Waxwing


Tardigrades (Water-bears) live in wet moss and lichens on ash trees (and everywhere else)


Nematodes and rotifers (in soil & wood)……

(Nematodes transmit Arabis Mosaic Virus)




Boletinellus merulioides (Ash Tree Bolete)

         A symbiont with the leafcurl aphid – exchanging housing for nutrients

         This mushroom has been found in Central Park (Manhattan), Prospect Park (Brooklyn), Alley Pond Park (Queens), Van Cortlandt Park and Pelham Bay Park (the Bronx), and Wolfe’s Pond Park (Staten Island)


Morchella angustieps (Black Morel)

         Found under dead and dying ash trees


Ash Tree endomycorrhizae…..(arbuscular mycorrhizae)…microscopic fungi living symbiotically within the roots of ash trees,

exchanging nutrients, like phosphorus, for carbohydrates. (Sequester carbon in soils)


Chalara fraxinea [Hymenoscyphus fraxineus] on Fr. excelsior (ash tree dieback) (other species?)


         “Endophytes in Ash Shoots – Diversity and Inhibition of Hymenoscyhus faxineus,” Hanackova, et al., Baltic Forestry 2017, vol. 23 (1)

                  Results: 58 fungal species (20 only in the summer, 23 only in the winter, and 15 in both seasons.  Species richness of saprotrophs decreased and species richness of pathogens increased in winter. Number of species was higher in the shoos of resistant trees than in susceptible trees (32 and 26 respectively).


Coral Spot on ash (Neonectria ditissima) on

Fraxinus profunda (and other ash species?)


Ash Anthracnose (Apiognomonia errabunda)

Also occur on oaks / causes leaf & twig dieback


Smooth Patch on Ash (Dendrothele macrodens)


Perenniporia fraxinophilus – large bracket higher up on ash trees…..”The major cause of trunkrot in living Fraxinus.” (N.A. Polypores)


Perenniporia fraxinea: a small white rot bracket near base of ash trees


Ash leaf rust fungus (Puccinia sparganoides)

         On white and green ashes. Secondary hosts

         are species of grasses – Spartina and Distichlis


Verticillium wilt: leaf wilt due to blocked xylem


Armillaria root rot fungus (Honey Mushroom)


Ganoderma root rot fungus (Reishi)


Laetiporus sulphureus: (Chicken Mushroom)

a brown rot pathogen; possibly nematocidal…


Oyster Mushroom (Pleurotus ostreatus)

         Feeding on bark, as well as nematodes…..

         (Many wood rot fungi consume nematodes!)


Inonotus hispidus : a shaggy, orange bracket that causes heart-rot


Pholiota squarrosa: a clustered, scaly, gilled mushroom, a decomposer


Lichens on Ash Trees

         536 lichens (plus 31 lichenicolous fungi, and 15 non-lichenized fungi) have been recorded on British Fraxinus excelsior trees



                           PROTIST KINGDOM

Many protozoans living on/feeding on algae, mosses, lichens and fungi on ash trees



Pseudomonas syringae (Bacterial Knot)

         on Fr. Excelsior


Ash Yellow (Candidatus phytoplasma fraxini

Causes witches’-brooms, slow growth, decline & early death: all Central Park spp. are susceptible



Arabis Mosaic Virus…transmitted by nematodes

(ArMV isolated from F. americana & F. excelsior)