I think this shrub planted outside the Stanley Park Pitch and Putt is Salix purpurea. How close am I to the ID? And those things? Is this a sick shrub, or what is going on? Thanks.
Salix yes, but not S. purpurea; that (unusually for a willow), has opposite leaves, which are also shorter, relatively broader, and with a less prominent midrib and 'softer' look.
Perhaps the material much grown as Salix purpurea cultivars has the incorrect species assignment. Here we can see both the type like in your picture and like in Wendy's photos, each returned as representing Salix purpurea: salix purpurea varieties - Bing images In North American gardens the prevalent version is 'Gracilis' ('Nana'). It produces a dense growth of many slender, purple branches, with slender, bluish leaves, and is often planted as a hedge. 'Pendula' has also been on the general market here, because it produces long, pendent branches I have it planted at the top of a wall on Camano Island. Because willow galls are said to be species specific that might pertain here, if Wendy can discover which species the galls seen are known to appear on.
I seem to have overlooked my homework assignment, but saw this shrub again and came to look for my posting. Do you think this looks like the Rabdophaga degeeri galls on Salix purpurea on this page? Insects on willows: gall inducers Or Rabdophaga rigidae, willow stem gall, shown at willow stem gall - Rabdophaga rigidae - BugGuide.Net. I've seen a lot more photos of the second one, with no willow species noted, except finally, here is an observation on a Salix petiolaris, meadow willow, which doesn't scream "wrong" to me, and is even native (though uncommon) to north-eastern BC, which we are not, but this is a Parks Board planting after all: willow beaked-gall midge from Peterborough, Ontario, Canada on September 14, 2020 at 08:46 AM by Don Sutherland. on Salix petiolaris · iNaturalist.ca Hey, that was this morning. Good thing I put off reviewing my photos for a few days. Salix petiolaris is within 1-4 m high, forms thickets, narrow leaves with entire margins, glaucous beneath, twigs glabrous, young stems appropriately yellowish to reddish brown. This is consistent with the description in Brayshaw, T. Christopher, Catkin-Bearing Plants of British Columbia, Royal British Columbia Museum, 1996, p. 84. I didn't remember this year to look for catkins. Well, I didn't remember anything about this until I saw the shrub with the galls again. Here are two new photos.
Here is a description of Salix petiolaris with several photos: Salix petiolaris (Meadow Willow): Minnesota Wildflowers They show a dried out midge gall, similar in shape, but I don't know that it looks exactly the same. It's bumpier. Not that I would ever veer off topic, but @Daniel Mosquin posted a pine cone willow gall, Rhabdophaga strobiloides, in the Botany Photo of the Day at Salix sp.. Great photo! You can tell those things on the shrub I posted are possibly not supposed to be there, but for someone who doesn't know willows, that pine cone gall looks like it easily could be a feature of the tree - it looks so perfect, so beautiful.
Having found no matching galls, I started to write that I was calling this Salix purpurea 'Gracilis' for now. Some photos of that show alternate leaves. SALIX purpurea 'Gracilis' Osier rouge - Arbuste (pepinieres-huchet.com) Purple willow Gracilis (aiglonindigo.com) Purpurinis karklas 'Gracilis' | Šilingų medelynas (silingumedelynas.lt) I mentioned S. petiolaris as a possibility in the previous posting. Then I remembered I now have a book: Catkin-Bearing Plants of British Columbia, Brayshaw, T. Christopher, Royal British Columbia Museum, Victoria, BC, 1996, which on pages 84-85 has Salix petiolaris J.E. Smith (S. gracilis Andersson). The leaves in the drawing look very similar (to the photos on the websites above and my photos) and are shown as alternate. Here's a page on this: Salix petiolaris - FNA (floranorthamerica.org). I seem to have missed seeing the flowers, or else it didn't flower. But it has a great new crop of galls. They were not yet present on May 20. When I next started to pay attention, on June 7, they were present. These photos are from four days in the past week, using two different cameras. I have given up now on getting these in focus.
I found a similar willow at UBCBG today, and after checking every willow in that area listed in Garden Explorer, I am pretty sure it's the Salix purpurea 'Nana' (no photos). The branching seems to be sometimes alternate, sometimes whorled (groups of three leaves). This one branch has a nice crop of aphids, white fly, and I think spider mites too, but that wasn't really very evident elsewhere on the plant. No galls, though. This looks the same to me as the one posted above, the subject of this thread. There was one next to this, with a label, Salix purpurea 'Pendula'. Now I have a question - Salix purpurea 'Gracilis' is not the same as Salix gracilis, or is it? The word "gracilis" is how I found S. petiolaris in my book, as it doesn't have S. purpurea. But the petiolaris description talks about stems turning black, not purple. The ones at UBCBG and in Stanley Park are clearly purple. It looks like I can go ahead with plan A and call this Salix purpurea 'Gracilis' or 'Nana'. Here's a great page on plant galls and rusts by host plant, but nothing looks similar to the galls here. Dorset - gall hosts S (dorsetnature.co.uk). Salix purpurea seems to be way down on the list of willows likely to have galls. The closest photo I've seen to a gall like this is Willow Beaked Gall Midge - Rabdophaga rigidae or Mayetiola rigidae. Here is a photo. Willow Beaked Gall Midge - Rabdophaga rigidae - BugGuide.Net (same website for this gall as I linked to above, but different photos). This is the only gall I've seen that seems to grow on the same part of the plant, with new leaves seeming to grow out of it.