Samantha Forster dug her fingers past the crust of garden soil, cooked hot by the August sun. She felt the cool dirt at the base of a plant. Was it a weed? She really hoped so.

Gram had assigned her to clear the vegetable garden of weeds, hinting that early morning was a good time to get started.

In shorts and a tank top instead of her usual boots and jeans, Sam worked in the shade of her white house, headquarters of River Bend Ranch.

Sam had awakened thinking of the river walk she'd take this morning with her foal Tempest. Her dreams had been filled with the splashing of tiny black hooves in the La Charla River shallows.

Sam hummed along with songs floating from the radio Gram had left on the porch. She felt cooler just picturing the wading horses, until the disc jockey broke into her daydream.

"If you're within the sound of my voice, brace yourself for the hottest week of the year. We're looking at a record 106 degrees by midweek and I call that a scorcher -- hot enough to fry an egg on the sidewalk, I'll betcha!"

Sam wiped her forehead with the back of one dirty hand.

"Only someone sitting in an air-conditioned studio could sound so cheerful," she grumbled to Blaze, who lay beside her as she knelt in Gram's garden.

The Border collie raised his head from between his paws, panted in agreement, then returned to his doze.

Snorts and squeals, the clacking of teeth and thump of hooves came from the ten-acre pasture. The saddle horses felt the high desert heat gathering. For several days, most of them had stood under the cottonwood tree at the far end of the enclosure. Now, their pent-up energy erupted in crankiness.

Shading her eyes, Sam searched the pasture for Popcorn.

The albino gelding stood apart from the others. His white tail swished at flies as he watched Penny, another captive mustang, enjoy pats and coddling from Brynna, Sam's stepmother.

Would the soaring temperatures affect Popcorn's usual calm with this week's HARP girls? The Horse and Rider Protection program brought at-risk girls together with captive mustangs. Though Sam thought it was a great program and believed River Bend Ranch was lucky to be part of it, the girls could be -- how had Brynna put it? -- oh yeah, a challenge.

A porch board squeaked and Sam looked up to see Gram fanning herself with the hem of her red apron.

On hot days like this, Gram began cooking in predawn darkness so she didn't have to turn on the oven later. As Sam rolled out of bed this morning, the aromas of fresh bread, brownies, cheddar cheese, and chili peppers had wafted up the stairs.

Flushed but satisfied, Gram said, "Baking's finished and the chili con queso is just simmering in the Crock-Pot. I'm about done for the -- Samantha, no!"

Sam snatched her hand back from the dirt and scrambled to her feet. What had Gram seen? A snake, scorpion, spider?

"That's better," Gram said. "If you hadn't loosened your death grip on my morning glory vine, you would have uprooted it, instead of that weed," Gram said.

"Sorry," Sam apologized. She almost wished a venomous pest had been skulking around her fingertips. She probably could have left off weeding for the day. "The point is to pull out the weeds that are gulping up the precious little water we can give the plants," Gram explained.

"Okay," Sam said, though the explanation didn't help much. To her, weeds and flowers looked a lot alike.

Green and spindly, they crawled over the dirt, then slung slender tendrils around the wire trellis Gram had put up. Higher up, the morning glories bloomed with blue, trumpet-shaped flowers, but when they were getting started, they looked just like the weeds.

"I know they all look alike at first," Gram said. "You have to learn to tell the difference. Water's precious. I save it for the tomatoes and green beans, corn and strawberries, because we can eat them."

"What about the roses?" Sam asked. She'd been thinking they were purely ornamental, but as soon as the words were out, she thought of Gram's rose hip tea.

"The roses are something of a luxury," Gram admitted. "Though my rose hip tea is full of vitamin C, and it's the quickest way to cure a cold." She looked at the trellis almost tenderly. "But the morning glories don't ask for much and they keep showing up on their own. Seems like the least we can do is clear away the weeds."

Sam nodded, but she still didn't really get it. Her only hope was to memorize the ones Gram pointed out as weeds.

Cackling and squawking, three Rhode Island Red hens flapped up a dust cloud nearby. Sam thought they were squabbling over the cracked corn she'd scattered for them earlier, until she heard Brynna's voice.

"You feel up to seeing the mustang colt from the Deerpath fire?"

Sam glanced up as Brynna walked toward her. With her hair pulled back in its usual red braid, and a sleeveless white blouse hanging loose over jeans, she looked more like a teenager than the manager of a government agency.

Brynna had been the boss at Willow Springs Wild Horse Center for three years. She acted as guardian and overseer of the wild horses that roamed the thousands of acres surrounding River Bend Ranch.

Brynna didn't look like anyone's pregnant stepmother, either, Sam thought, but she was that, too.