There are some Australian species that are tied to chemicals in smoke to germinate but the list of genera that really require smoke is quite small. There are others where smoke treatment lifts germination by a few % but most don't seem to need smoke. The relevant chemicals are water soluble so we can now purchase 'smoke water' to help with germination. Needless to say the marketers of the stuff tend to hint that many other species will benefit. Seed can be home smoked if you want to try it. Sow seed in trays as normal. Light a small fire in a drum large enough to hold the seed trays. Place seed trays above the smoking fire and place the lid on the drum to trap the smoke. Fire will go out because of lack of O2 but should still produce some smoke. Leave the trays to soak in smoke for a couple of hours then remove the trays to normal germination area. Anyone with a cool meat smoker could simply smoke seed trays in the smoke chamber. The aim is cool smoke as for bacon and ham not hot smoking like fish.
Smoke water is made by passing smoke through a container of water - vaccuum cleaner as suction and hoses to connect fire chamber with water container. Smoked water can be stored for later use.
Small white 'bottle brush' flowers is probably a Melaleuca sp. They come in all shapes and sizes but flower shape and arrangement is similar.
Lime scented paperbark is Melaleuca squarrosa. It's an Eastern Australia species, more common in Tasmania so could be more cold tolerant than many Western species.
Just looked up Melaleuca germination in Murray Ralph - Growing Australian Plants from seed where he notes that M ericifolia and M lanceolata germination is significantly increased with smoke treatment and may also be successful with other sp. Many Melaleuca sp need light to germinate so sprinkle seed on the surface only.
There are many small, shrubby Banksia sp but I can't find ref to Shrubby Banksia as a common name so not sure what that might be. All banksias produce seed in hard follicles on 'cones'. Some open and shed seed at maturity but others remain firmly closed until the tree dies which usually means bushfire. We extract seed from these stubborn cones by roasting them on a fire or BBQ but the seed itself does not respond to smoke and will germinate without treatment.
Casuarina genus has been split into Casuarina and Allocasuarina. WA has some of each as well as some Eastern species that have naturalised and become weeds there. Both Allocasuarina and Casuarina are similar in growth and requirements so the name change is not really important to us as growers. No treatment required for any species
'Silver Princess' is a form of Eucalyptus caesia. I don't suppose you went out to see Eucalyptus caesia in its natural habitat? We drove nearly 800km out to Elachbutting rock just to find some in the wild. They only grow at the base of large granite outcrops in the semi desert wheatbelt of WA. Beautiful trees but, unfortunately, do not tend to live long outside their preferred habitat. Over here they live 3-5 years before declining.
Seed should be easy to germinate.
Good luck with the Sturt Desert Pea. I've tried a number of times and have never succeeded in getting one to flower. Seed has a hard, water resistant coating so needs treatment to get good germination. Boiling water is the easiest. Boil a kettle, place seeds in a cup and half fill the cup with boiling water then leave the seeds to soak overnight. Drain and sow as usual.
Natural habitat is deep, sandy soils and the plants have a very long tap root and do not transplant well. They seem to do best when grown in tall, bottomless pots or earthen pipes placed vertical in the garden and filled with soil.
