There is a bright yellow dawn redwood called Gold Rush. You should be able to find one that is not that expensive. You could also try a Northern Bell Sweetbay magnolia. David

For standing water I would recomment you a Taxodium distichum 'Pevé Yellow'.
It's a Dutch selection from Piet Vergeldt and is also availlable in the U.S.

Yes, the Taxodium's come to mind. 'Mickelson' same as 'Shawnee Brave' which is the more expensive patented name is a great fall color and beautifully branched Bald Cypres.

Here's a list I have of plants that can be planted directly into water as small seedlings being the very best bet for you/small grafts. Bare-root them and tuck the roots into place into made crevaces of your clay.

Dax

Notes with Quotes:

Water tolerant Trees/Shrubs: "You can plant direct into the soil at the bottom of the pond, as long as it is not more than 50-60cm deep water." (Resin)
"I think the edge is your safest bet. If you go deeper, try to use small bare root plants that have not been grown in a container or in upland soil in a nursery for very long." Guy Sternberg
Taxodium distichum, Nyssa aquatica, Salix, Carya aquatica, Forestiera acuminata, Planera aquatica, Nyssa ogeche, Itea virginica, Quercus lyrata, Larix species, Sycamore.

Dax

hey simon..

you just bought this house .... yes???

i dont understand how you know there is standing water there all summer long??? ...

how long does it stand .. and how pervasive it is.. will make a big difference ...

you have 2 acres... and you have swampy ground... think willow.. might get rid of the water altogether ...

otherwise.. you may need to take a year to figure out your new property ... to see how it all works ...

i wouldnt be in too big a hurry ..... unless you like making mistakes ... or wouldnt mind admitting mistakes and moving or killing stuff in the future ....

in z5 ... there are two planting seasons.. mid april ... and october .... so you can do your planting in fall... if necessary ...

ken

We have standing water and gently flowing water.

Bald cypress, dawn redwood, prairie cascade willows, sweetgums, water tupelo, cottonwoods do very well.

Thuja plicata on the edges would thrive. We also planted giant sequoias plop in the middle of little creeklets and they are also doing really well.

Many trees we put in creeklets died of too much water, including coast redwoods and sitka spruce which we thought would survive.

It's true that if a tree is older it has a harder time adapting to new conditions.

Our 3 Nyssa aquatica are supposed to be slow growing but are shooting up nicely. Really stunning fall colors. And the sweetgums are also growing faster than advertised.

We have some native Aspens that seem to like water and 2 October Glory maples in creeklets that are thriving. These were very small when planted.

We have a native redtwig dogwood, Hedgrows Gold, that is amazing in water, absolutely stunning leaves and bright red branches. We like it so much this Saturday we're going to the nursery in Mcminnville that introduced it to buy a lot more little plants. We learned that we had to experiment to see what survived, and then plant more of the survivors that we liked.

Hands down the Prairie Cascade Willow is the most amazing strong fast hardy of any of the 25 willows we've tried, and LOVES water! It already has huge roots plunging straight down into the deepest parts of the creeklets. Big golden bright branches in winter and big glossy green leaves in summer. Cannot recommend this tree enough.