Prunus mahaleb & Acer ginnala - are they sick?

[Krone]

Can someone please tell me what are these weird dots on my prunus and acer? Also, leaves on prunus have some light green spots and couple of theam have some weird 'things' at the 'neck' (sry, can't remember the correct word in english).



The 'neck' thing...



Thanks guys!

 

[NOZZLE HEAD]

It doesn’t look like any disease I am familiar with.

If those symptoms showed up over night and are not spreading, then I would point the finger at an abiotic factor.

 

[Krone]

I have first noticed it couple of weeks ago. First i thought that maybe it is a slight sun burn, only yesterday i have noticed the larger brown spots and the spots with lighter color.

 

[sorce]

Looks like scale in the neck or petiole. (I like neck better!)

The drips are from the sucking, the scale is probably smaller, yellow, and hiding mostly in the ridge.

Sorce

 

[Krone]

Regarding the stuff on the neck (petiole is the word), have gotten the information that this are petiolar glands.
And they are not drips but are in solid form.

 

[parhamr]

The prunus leaves appear to me as though they might have a mild rust or leaf spot type of infection. Since prunus is one half of the nearly unavoidable cedar-apple rust I tend to give them prophylactic sprays: an antifungal at least once a year (chlorothalonil, thiophanate-methyl, and Mancozeb each work well) and something that knocks down the spores no more than three times a year, e.g. copper or sulfur compounds.

 

[ralf]

The light green spots on leaves are very often related to spider mites or scales activity -sucking the sap - as sorce sugested. You may check the underside of the leaves for the bugs or perhaps their nymphs.