I do have a tip for bracken fern - use scissors or a string trimmer to cut the emerging fronds off at ground level on a warm day. The fern will continue to pump moisture up from the roots and this helps to kill the roots and all. You may need to repeat several times before the root system dries up. As for California cucumber I have no experience with this weed but all plant life needs sunlight. You can cut back any plant to ground level, cover with cardboard or newspaper and then a few inches of mulch like wood chips or even heavy bricks or rocks to keep out all sunlight. This will starve the root. You can also try the cut and cut again method of weed control. Just keep mowing or cutting the plants to the ground every few days until you weaken the root system and the weed gives up. Not easy but effective. Don't be discouraged we all have weeds but overcoming a challenge is part of the joy of gardening. Keep growing, Marianne Binetti