LARA AND JOE VISIT THE FARM
by Sue Alender
Prologue
Lara and Joe watched the houses flit past the car windows.
“Are we almost there yet?” Joe asked.
Mom and Dad laughed. Joe was too old to ask that question, but as the impatient one, it was his traditional job to ask. Lara looked back to her book. She knew that soon the houses would spread farther apart, and the fields and woods would stretch out, and Gramma and Grampa’s house would welcome them. This would be the first time that she and Joe would be staying for the whole summer without their parents.
Chapter 1
GROWING PLANTS
(Abiotic Factors Affect the Rate of Photosynthesis)
“Good morning! Time to get up and get to work!” Gramma called.
Lara’s clock showed 7:00 am. She got out of bed without groaning. After all, it was only for 8 weeks, and Gramma and Grampa were set in their ways. She dressed and went down to breakfast, expecting to find Joe in front of the TV.
“Where’s Joe?” she asked, finding the house empty except for Gramma.
“He’s been out helping Grampa in the shed. They’re setting up the irrigation today. We haven’t had a June this dry since your Mom lived with us.”
Suddenly, Lara pushed aside plans to sneak off and read. She hurried through a bowl of cereal to get out to the action. As she stepped out the door and turned her face into the wind, she noticed the straight rows of strawberries in the field near the house, and then gazed off at the curving rows of stunted corn on the hillside. The faint odor of manure bothered her nostrils. She ran out to the shed.
“Grampa, what happened to the corn?” she asked breathlessly.
“Well, Lara, I know it’s small right now, but once we get the irrigation set up, it’ll perk up and grow fast in this sunny, warm weather. Gotta give things what they need to grow.”
WATER
Joe added, “Grampa set up the irrigation for the strawberries a few weeks ago, but I’m helping with the pipe for the corn.”
“Why do you need to irrigate, Grampa? Can’t you just wait until it rains? I mean, I know the strawberries needed water already, because they only grow their berries in June and early July, but you don’t cut the corn until September or October,” Lara pointed out. It seemed like an awful lot of work when everyone knew it would rain eventually. Grampa and Joe continued loading irrigation pipe behind the tractor.
Grampa replied, “You’ve got to understand plants, Honey. A plant needs water to make its own food. Without water, it will starve.”
“No, Grampa. You’re wrong,” said Joe. “Plants drink from their roots. I learned that in school. They don’t have any mouth to eat with.”
“I know what you mean, Grampa,” said Lara excitedly. “I read about it for school. Plants do make their food with water – it’s called photosynthesis. They need water, and carbon dioxide, and sunlight on their leaves, so they can make a kind of sugar for their food, and then they get rid of oxygen through their leaves. You see, Joe, they don’t need a mouth, because they make the sugar in their leaves, so their food is already inside them.”
“Hey, that’s pretty smart,” said Grampa. “So, if they don’t have water, what we see is a plant wilting. What is happening is the plant slowly starves, living off whatever sugar it has stored. It can’t grow bigger if it doesn’t have food. So if I don’t irrigate the corn now during its growing season, it won’t be fully grown by the time I have to cut it in the fall. Now hop on the tractor and we’ll drive up to the cornfield.”
SUNLIGHT
“How come the land looks different here than in the suburbs, Grampa?” Lara wanted to know. “I mean, there’s lots of open spaces on a farm – you can look around and see a long ways. Around our house, there are so many trees, you kind of feel hemmed in.”
“What grows under the trees?” Grampa asked as he started unloading the irrigation pipe.
“Some scrubby bushes and little prickery viney things,” Joe blurted out.
“What do you think would happen if I brought my tractor to your woods and planted my cow corn underneath the trees?”
Joe said, “You couldn’t fit your tractor in. There are too many roots and trunks and rocks and stuff.”
Lara responded, “And you wouldn’t be giving the corn what it needs to grow, right, Grampa? If it can’t make food without water, then it can’t make food without sunlight! The trees would steal the sunlight from the corn, and it would be all starving and sickly-looking.”
Grampa laughed out loud this time. “I don’t know about stealing sunlight. I think sunlight doesn’t really belong to any one plant, but you have the idea. I have to plow the fields and keep them clear so the corn can get all of the sunlight it needs. Because corn needs more sunlight than those little prickery things that grow under trees.”
Lara had been thinking more about the corn. “Why do you cut the corn in the early fall, then? If more sunlight makes more food, shouldn’t you leave it longer to use all the sun it can?”
“Well,” Grampa replied, “the only problem is, the corn uses some of its food, too. As long as the sun is bright, it makes more than it uses, so it stores some. When the sun changes its angle in the fall, the sunlight is weak when it gets to us. The corn keeps on using food, but it doesn’t make enough to keep up. That’s when I have to cut it.”
Joe turned his face towards the sun. “Oh, you’re kidding.” He slapped his leg. “Oh, you have GOT to be kidding!” he repeated. “I can’t believe this – plants need sun to make their food by photosynthesis.”
Lara thought he was going crazy after one morning without TV. “That’s what we’ve been talking about . . .”
“No, I mean, I know we’ve been talking about it, but I just understood what that TV show was talking about. The one that said dinosaurs became extinct because of a meteor hitting Earth and sending dust into the air. I was thinking that dust couldn’t give dinosaurs asthma so bad to kill them all, so I never believed it. They meant that the dust blocked out the sunlilght, so the plants couldn’t make food, so the dinosaurs eventually ran out of stuff to eat. Now I get it!”
Grampa chuckled again. “So I give my plants water and make sure they have sunlight, but one good thing about that photosynthesis is – the air gives them all the carbon dioxide they need.”
CARBON DIOXIDE
Joe laughed. “If you had to give them carbon dioxide, too, you could hire Lara to stand out in the fields and talk at them all day!” Joe thought this was entirely too funny. He dropped the pipe he was carrying.
Lara wasn’t amused. She picked up the pipe and carried it the rest of the way down the field. “Well, I’ve read about experiments where people talk to their houseplants and they grow better. I guess those people were thinking it was the talking that made the plants grow, but maybe it was just the extra carbon dioxide.”
“Could be. I can’t say about that,” Grampa said. “I never tried talking to my corn. I try to save my words for you two.”
TEMPERATURE
Lara and Joe trudged back to the tractor for more pipes. It was only 8:30, and they were already sweating. Joe said, “Grampa, isn’t it getting too hot to work?”
“There is no such thing as too hot for a farmer to work. We might be more comfortable if it was cooler, but then the crops wouldn’t grow as fast, and the strawberries wouldn’t be so sweet.”
“Because of the sun?” asked Lara. “When it’s sunny, that means it hot, right?”
“Partly, but also partly just because of the heat. You know how you feel more comfortable when it’s a little cooler? Well, plants do that photosynthesis faster or slower depending on their temperature, too. Each kind of plant has a temperature that’s ‘comfortable’ for its own self. If it gets too cold, photosynthesis slows down. When it gets nice and hot, photosynthesis speeds up. But if it gets too hot, the plant just dies – it kind of cooks. Hot for us is just what the corn likes, as long as we give it some water.”
NUTRIENTS
They walked back down the row to get Grampa’s tools. “So that’s pretty simple, really. Plants just need water and sunlight and carbon dioxide (at the right temperature) to make sugar, which is their food,” summarized Joe. “But I think you’re forgetting something, Grampa. Why do you spread manure on the fields? It seems like a lot of smell and an awful lot of work if the plants don’t need it.”
“Well, I said to make food, the plants use water and carbon dioxide and sunlight. To grow more leaves and longer stems, they need nutrients. Like with kids, the energy you need for playing or working is different from the materials you need for growing. You can go play for half an hour after eating a candy bar, but we make you drink your milk for growing bones and eat your meat for building muscles. Plants, like kids, need nutrients to grow bigger. Their roots get those nutrients from the soil, and the soil gets those nutrients from the old manure I spread on the fields in the spring.”
Lara added, “Nobody spreads manure on the little prickery things in the woods, and they grow.”
Grampa’s eyes twinkled. “Are you sure nobody spreads manure in the woods? What about the birds and the squirrels and the worms and bacteria? They’re all returning nutrients to the soil.”
“I didn’t think about that. It makes sense, though. What about some of the other things you do on the farm – like hoeing?” Lara shuddered slightly. She didn’t like hoeing.
“You hoe to get rid of weeds. Why should you get rid of weeds?” Grampa asked.
“I know!” shouted Joe. “The weeds would grow really big and steal the sunlight from the crops, right?”
“Partly.”
“And as the weeds grew, they would take the nutrients in the soil that you wanted to give to the crops, right?” he added.
Grampa finished connecting the irrigation pipe and stood up slowly. “You know, I think you’re going to be smart like your sister. We hoe the strawberries, but there’s too much corn to hoe. So I cheat a little and spray it with herbicide to kill weeds and with pesticide to kill bugs that would eat the corn. And this year, I’m growing science fiction corn.”
“Science fiction corn!” exclaimed Lara, thinking of H.G. Wells. “It’s not science fiction – it’s right here in front of us!”
“This strain of corn didn’t exist twenty years ago. I’m growing genetically engineered corn now. Scientists cut into its DNA, put in a special gene that made it resistant to herbicides, and made a new kind of corn. Now I can spray a little chemical on the field to kill the weeds when the corn is little, instead of having to use a lot of spray before the corn comes up.”
Lara felt a little guilty about disliking hoeing. It all made sense now. Hoeing was a way to protect the crops from competition. One last thing bothered her, though.
“Grampa, who plowed the hillside? The strawberries on the flats are plowed all nice and straight, but whoever plowed the cornfield wasn’t paying attention – the rows are all curving,” Lara explained.
Grampa chuckled. “Actually, Lara, I plowed like that on purpose. It’s called contour plowing. If I plowed straight up and down the hill, the furrows would be little streams when we ever do get rain. The water wouldn’t have time to soak deep into the ground for the roots to drink, and the soil with all the nutrients would wash away. You know, there are some places where farmland is so scarce that farmers have to make it into terraces, or steps, so there’s some small bits of flat land to grow crops on. I guess farming might look confusing, but it’s all common sense, based on science.”
They rode the tractor back to the yard, and Grampa turned on the irrigation pump. The connections didn’t leak. The water oozed out around the corn plants. Joe thought he could hear the corn plants drinking through their roots and saying, “Aaaahhh”. Then he imagined that they were doing photosynthesis and making sugar, and he imagined them saying, “Just like a candy bar!”
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