Plant ecosystem is an orderly process of ecosystem development.

Answer

### Step-by-Step Solution:

1. **Understanding the Statement**: The statement claims that "Plant ecosystem is an orderly process of ecosystem development." We need to determine if this statement is true or false.

2. **Definition of Ecosystem Development**: Ecosystem development refers to the gradual process through which ecosystems evolve over time, starting from a barren or disturbed area and progressing through various stages until reaching a stable state.

3. **Pioneer Species**: The first organisms to colonize a barren land are known as pioneer species. These species are crucial for initiating the ecosystem development process. An example of a pioneer species is lichens.

4. **Stages of Development**: After the pioneer species, the ecosystem progresses through several stages:
- **Herbs**: Following lichens, herbaceous plants begin to grow.
- **Shrubs**: Next, shrubs start to establish themselves.
- **Small Trees**: After shrubs, small trees may begin to grow.
- **Larger Trees**: Finally, larger trees can establish themselves, leading to the formation of a forest.

5. **Climax Community**: The final stage of ecosystem development is known as the climax community. This is a stable and mature ecosystem that can sustain itself over time.

6. **Conclusion**: Since the development of a plant ecosystem follows a specific order and process, the statement "Plant ecosystem is an orderly process of ecosystem development" is true.

### Final Answer:
The statement is **True**. The development of a plant ecosystem follows an orderly process, starting from pioneer species and progressing through various stages until reaching a climax community.

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