Objective: To develop students’ understanding of the relationship between the plant organism and environmental conditions, to form the ability to identify early flowering plants.
Objectives:
1. To develop materialistic views on the nature, on the example of local flora in the spring to reveal its diversity, highlighting the most important signs of the adaptability of grasses, bushes and trees;
2. To establish the reasons of early flowering of woody and herbaceous plants and the change of seasonal phenomena in plant life on the example of local flora in the spring period ;
3. To acquaint the students with the different periods of spring.
4. To form a careful attitude towards nature;
5. To promote aesthetic education of pupils by means of nature and art.
(I have chosen the following route: the school garden. I think it is a good place to study trees, bushes and grass).
The equipment I need: a photo camera, a notebook, a pen, pencils and a folder.
1. Teacher’s introduction.
In class before going on an excursion the teacher informs the purpose of the excursion and the plan-route. The scheme of the route is considered on the board with an explanation of the stops, then students redraw it in their notebooks. The assignment questions need to be commented on. Pupils are divided into groups of two to four (depending on the number of pupils). They are given the necessary material.
Talk about changes observed in nature in the spring.
The laws of nature act like a “clock”, namely: Usually 8 days after the flowering of mother-oil and stepmother, in 21 days the dandelion and willow will blossom. The pear blossoms on the 29th day, the acacia on the 30th, and the linden on the 75th day after the beginning of mother-and-ginger flowering.
What natural phenomena can you observe in the spring? (Sap movement, swelling and opening of leaf and flower buds, flowering of early-blooming plants, shoot growth).
What causes cause these phenomena to occur? (Increased air temperature, longer daylight hours, root uptake of water with mineral salts dissolved in it, movement of plant reserves to growing plant organs).
Life of herbaceous early flowering plants in spring.
Which herbaceous plants bloom first in the spring? (Mother and stepmother, honeydew, primroses).
What is a prerequisite for early flowering of plants? (The inflorescences are set in the summer of the previous year. The stock of nutrients is concentrated in the rhizome).
Where do you find mother-and-bloodwort? (In some places there is still snow, and where the sun warms up, on slopes, hills, on open lighted and heated places. As soon as the snow melts, its leafless stems with bright yellow inflorescences appear).
What is the name of the inflorescence of this plant? What are its characteristics? (A basket is a compact inflorescence of small flowers.)
How does the mother and stepmother pollinate? What signs do you use to determine this? (By insects, but self-pollination can also occur.)
Why does this plant bloom so early? (Plenty of nutrition is needed for it to flower. This plant does not have green leaves yet. The nutrients are stored in the rhizomes. This organ of the plant is mentioned in the riddle: “There is a string in the ground, and in it is a pantry.
To which plant organ does the rhizome belong? (Modified shoot).
How do you prove this? (The rhizome contains a store of nutrients. It is deposited last summer. These stores make flower buds grow and fruits form. Then the plant has large leaves).
Why is the plant called “mother and stepmother”?
(Try to put to your skin alternately the lower and upper sides of the leaf, in the first case you will feel heat, and in the second – cold. This explains why people from ancient times called this plant mother and stepmother).
What is useful for this plant? (This is a medicinal plant. Collected leaves are used for respiratory diseases).
What is the importance of the pubescence of the stems and young leaves of mother- and stepmother? (Pubescence protects the leaves and stems from freezing and excessive evaporation. A protective layer of air is formed between the hairs).
On clear spring days, these plants turn yellow with golden stars. But as soon as a rain cloud appears in the sky, the stars go out – the flowers close up. This is how Mother Stepmother predicts the weather.
Tufted buntings bloom early in the spring. Stock of nutrients they have in the underground tuber. They are undemanding and frost-resistant.
How is it possible that the coneflower is so rapid in its development? The snow has only just fallen. And it is already blooming! As if appeared out of nowhere. And he sits in the soil at some depth – rounded, yellowish, the size of a cherry. On the nodule – a bud. Even in winter, a sprout forms from it. Outside it is dressed with a translucent protective cover. By the beginning of spring the sprout has almost reached the surface. As soon as it looks out into the sunlight, the sheath bursts and falls away. The plant looks like a bud at first: the stem is bent and the leaves are curled in a clump. But soon the crested plant straightens, unfolds its tracery leaves. And it is ready to bloom.
Why do all firstflowers rush to bloom? (All of these plants are light-loving and bloom before the leaves on trees and shrubs bloom, when there is plenty of light in the forest.)
Early flowering herbaceous plants have nectar, edible sticky pollen, and some have brightly colored corollas.
Woody plants in spring.
The early and late spring is a good time to begin to awaken to the wild life hidden from our eyes and ears. The winter snow is melting. Above head thin branches of birches overgrown with resinous buds are seen. More and more bird voices are being heard. One smells the resinous buds, the bark of the trees. The trees have a sap movement in the spring. Blossoming of the buds, flowering.
How are woody plants pollinated? (Alder, aspen, birch, poplar are wind-pollinated. Willow is an insect-pollinated plant.)
Independent work of students on studying natural objects according to the plan
Task 1.
At the first stop, fill in the table.
| Time of the year | Day length | Air temperature | Illuminance | Presence of clouds | Height of the sun above the horizon |
Compare the phenomena observed in spring with other seasons (fall, winter). Describe the periods of spring.
Assignment 2.
On an area of 10 m2 determine the number of flowering specimens of herbaceous plants. Compare the number of plants blooming in an open and a shaded area. Identify the reasons for the difference.
Assignment 3.
Identify the differences in growth and development of annuals and perennials (herbaceous plants) using the following features: height of plants, presence of leaves, their number, form, size, coloring, pollination methods, presence of roots and underground organs (the plant in question should be compared to the herbarium specimen). Record the data in the table.
| Characteristics of plants | Plant names |
| Lifecycle length | |
| Place of growth (air temperature, illumination) | |
| Presence of flower | |
| Leaves | |
| Root system |
After completing the table, answer the questions:
– What are the characteristics of early spring plants (number, size, frequency of occurrence, flowering, appearance of leaves, coloring of flowers, insect visits)?
– What are the reasons for the rapid growth and development of early spring plants (nutrient supply, location, availability of spring moisture, heat, light).
Assignment 4.
Identify adaptive traits to adverse conditions (sudden changes in weather, temperature, wind, snow).
Assignment 5.
Identify pollination adaptations of annual and perennial herbaceous plants that bloom in early spring.
After completing five tasks, answer the question: what are the biological features of herbaceous early flowering plants? Write down the answer in the notebook when making your field trip report.
The game “Find Changes”.
Each group is given the task of remembering all the natural objects that are on a given site. Teams switch sites and make up to five changes at the other group’s site (e.g., swapping objects (rocks, fallen tree branches, etc.)). Teams return to their areas and try to find all the changes. This game develops attention and memory and helps to memorize the objects of wildlife better.
The game “Listen to the Tree”.
You can use a medical phonendoscope to listen to the trees. In April, it is possible to hear the sap movement of the birch and maple. Hearing the sounds helps you understand that the tree is alive!
Final Talk
Reflection at the end of the excursion.
– What was the most interesting part of your excursion?
– How easy or difficult was it for each of you to do the tasks?
– What time of year do you like the area of the educational institution the most? Why?
– What did you learn about the territory of the educational institution?Homework. Make a report in your notebooks about the excursion according to the suggested plan on the task cards.
