Hi there - thanks for your replies earlier. Since it started raining, my weeping cherry has masses of gelatinous goop coming out of the crown of it's branches. It is dropping in blobs onto the dirt below. This goop isn't sticky, it's more like jelly. I've included a picture, but now the blobs are much bigger, like popcorn. I've covered the soil of both trees with plastic to prevent further water-saturation, but am seriously wondering if this is more than that. I've never seen this tree leak golden gel before. Is this a bacteria? Thanks, Megan
The production of goo, is technically known as gummosis (abnormal production of gum), is the plant's response to infection. The goo is a natural product produced in the tissues of the cherry tree. The tree is essentially trying to wall off the source of infection. Unfortunately, the cause is probably the bacterium that causes bacterial canker, which becomes systemic in the cherry tissue. In other words, the tree hasn't really got a hope in isolating the pathogen or the damage. On the other hand, the tree may grow perfectly well and continue to produce the gummosis for a number of years with the disease. Brown rot fungus (which causes a blight of flowers and the softest new growth in spring) is another common cause of gummosis.
Yes, someone else mentioned blight to me, fireblight specifically due to the very wet conditions we've had and probably becuase it's sitting in a pot rather than planted. Is there any treatment for that at this point, or is it too late? Thanks very much for your help, Megan
My understanding of what Douglas wrote is that it's never going to be a very healthy tree, but there's some chance that it could be a tree and do its flowery thing every year. What are you up for? I don't think there's a treatment for gummosis - the tree either figures out how to live with it or doesn't. If you're keen to see if it can pull through, then keep it until you see what the flowers look like next year. If the flowers and new growth are damaged, then you'll get more enjoyment from something that looks healthier.
And just to clarify: Fireblight is disease caused by a different bacterium (Erwinia amylovora), and although it can attack Prunus and other stone fruits, it is much more common on crabapple relatives, such as pear, cotoneaster and mountain ash. It isn't particularly common in Vancouver, as it requires moisture + warm temperatures (≈20C) + susceptible tissues (e.g., flowers). Brown rot, which is a fungal disease common on stone fruits, including cherries, attacks similar tissues, and also causes blight (rapid death of whole shoots). It is typically caused by Monilinia fruticola, as well as other Monilinia species. The incidence of brown rot escalates in susceptible species with increasing moisture duration, temperature and the supply of inoculum (i.e., the availability of infective spores, which are air-borne). However, the optimal temperature range for infection by brown rot is slightly cooler than for infection by fireblight, and moisture duration is a more important factor. In other words, the longer that tissues are wet, regardless of temperature (within an effective range), the greater likelihood of infection. Infected tissues are the most common source of inoculum, so it is prudent to prune off diseased twigs and mummied cherries in summer.
