Magnolias are so old that they're pollinated by beetles, not bees (2025)

You must have caught it within two or three hours after its arrival.

In the US we have similar hawk moths; the tomato hornworm also looks like a hummingbird when it reaches maturity.

Probably a flush of nitrogen at exactly the wrong time tho. Most plants respond to that by pushing excess green growth instead of flowering and fruit set.

Also, southern Ontario.

would not rule out the cash crop farming on both sides of me from doing a number on the insects, though i seem to have plenty overall.

unfortunately an excessive number of japanese beetles

So there is no doubt that the immediate ancestors of bees were predatory, like also their more distant ancestors that they share with ants and other kinds of wasps.

Hymenoptera has split early into two branches, one leading to wasps and the other to sawflies.

Most sawflies, as you say, feed on plants. So the question is what kind of food was used by the common ancestor of all Hymenoptera, given that from that ancestor there are two descendant groups, one predatory and one phytophagous (plant-eating).

There is no certain evidence for this, but there are arguments that it is much more likely that the common ancestor was predatory and the sawflies have evolved from that into plant-eating insects.

There are two arguments for this. One is that eating plants is more difficult for animals and all plant-eating animals had to develop special abilities in order to digest plants. Because of this there are a lot of examples among animal groups where the ancestors of a group were predatory, and only some of their descendants have succeeded to transition to feeding on plants.

There are much fewer examples of plant-eating animals that have become predatory again, because once some animals become able to eat plants, they normally have access to a much more abundant source of food than the predatory animals, so reverting to a predatory lifestyle would be disadvantageous. Humans are one of the few exceptions, because their ability to throw weapons at a distance has allowed them to become extremely successful hunters.

The second argument is that Hymenoptera form one of the two branches of Holometabola, the insects with complete metamorphosis. For the orders of insects that belong to the other branch of Holometabola, e.g. for beetles, wherever there is reasonable certainty about the lifestyle of the ancestors, they were also predatory, so it is more likely that the common ancestor of all Holometabola was also predatory.

https://www.nature.com/articles/nrn3357

Note there are various species who're oligolectic meaning they only collect pollen and nectar - and hence pollinate only - a single family or sometimes even single species of plants. Moreover they are usually also better at pollinating than more generalistic species especially honeybees.